BA with Linux, is possible ?
yup, check the wiki. there are links there regarding linux on PPC.
xykosomatik said:
yup, check the wiki. there are links there regarding linux on PPC.
Click to expand...
Click to collapse
I usually give the links if I know where they are available. Saying Google it, or refer to WiKi doesnt sound nice to me, I prefer to keep quite in such cases.
http://rtfm.eu/
Referring to wiki sounds good to me
Linux mobile, yes but this future os for mobile device. You can find information it in Google search.
http://linuxdevices.com/news/NS7689617070.html
April 1 said:
I usually give the links if I know where they are available. Saying Google it, or refer to WiKi doesnt sound nice to me, I prefer to keep quite in such cases.
Click to expand...
Click to collapse
give a man a fish, he'll expect you to give him one everyday of his life. teach that man how to fish, and he will improve his life.
Here you can see the status of Linux on BA.
http://handhelds.org/moin/moin.cgi/BlueAngel
May be, in a future, we could forget Windows on our BA and start controlling what it happens inside it.
I think if people like pof, mdaiiiuser, helmi, xplode ... start using Linux on the BA we could also start and cooperate getting a relly working device, not a brick with linux inside.
There are other options/projects, like OpenMoko, Androik, OpenEZH but I think it's better to wait for a winner and a really open and usable device.
So I will maintain my BA until it work on Linux or gets broken.
Related
Well, it's more than just questions.
I have the HD2 and I really enjoy it. Think it's a great piece of hardware. WM6.5 gets the job done for the most part, but I can understand some of the concerns with the OS. It's good to hear that you guys are already working on WM7 and the port to this phone!
Truth is, I put my coin in google's corner, so I'm hoping that Android finds its way into the HD2 via T Mobile.
I'm a bit tech savy, been involved with computer animation and can build computers as well. I thought I ask about the learning curve when it comes to development on PDA's such as mine. With the drop of Android, I flirted with the idea of learning code.
Is Android Linux based?
You guys hear anything about Android getting a port to this phone? I've done the google search and can only find the sprint version of HD2 with Android installed. That does nothing for TMobile customers.
I read up a bit on XDA and they appear legit. My concern is code being used for identity theft. Anyone have bad experiences with XDA and the software that is released here for share? Does the software under go some sort of QA before it's provided for download?
I have no problem with donations, trust is what earns my donations...fair enough, right?
Ultimately, I really like this phone and look forward to further enhancing it...I hear XDA is the place to be!
Thanks guys/gals.
FAQ's and sticky threads are your friend as is google.
Try reading abit, get a feel for the site.. Then ask..
Yes Winmo7 is being ported to the touch HD, though at the moment it's sluggish due to lack of graphical acceleration (and not really something i"m excited by since it doesn't have copy and paste and no multitasking. IMHO it's really more like an iphone/toy meant for none-techy people).
I don't expect an official update/ROM for the HD2 with android to ever be released by htc/tmobile. However, I would be surprised if one wasn't ported by xda from other devices (like nexus/evo 4g).
Yes, android is unix based. (develepment done in java (for upper stuff) and C (for lower stuff)).
Anything you download and install from xda you do so at your own risk. However, I would argue that the risk is minimal (almost none existent) as long as you follow directions and read posts. The only thing that can brick your phone is a failed radio/SPL update/change. Anything else can be cured by a hard reset.
(and what kable said)
As unfriendly as my reply may seem, for a "tech savvy" guy you asked several questions which would have been abundantly answered if you properly used the search tools of the forum, or if you simply browsed through the most active threads
ephestione said:
As unfriendly as my reply may seem, for a "tech savvy" guy you asked several questions which would have been abundantly answered if you properly used the search tools of the forum, or if you simply browsed through the most active threads
Click to expand...
Click to collapse
Thick skin...you grouches don't faze me
I've been through the site a bit, what can I say, life outside of the computer caught up and I got a little impatient!
I'm still reading through the forum. Have yet to find an answer to this question.
If I install Android on my HD2 (US), something goes wrong...will I be able to do a hard reset, or reinstall WM6.5?
I really think Android would benefit more out of this hardware. It seems as if everything Unix based always requires less resources and gets the job done!
I also would like to know how I can uninstall these game demos that are eating up space? Will this be a registry edit?
I feel as if Android would FLY on this device. WM6.5 is getting the job done, but it's to late for Microsoft with me. I've used Linux for some time and I just think it's better. Huge supporter of Linux!
Devils1stBorn said:
Thick skin...you grouches don't faze me
I've been through the site a bit, what can I say, life outside of the computer caught up and I got a little impatient!
I'm still reading through the forum. Have yet to find an answer to this question.
If I install Android on my HD2 (US), something goes wrong...will I be able to do a hard reset, or reinstall WM6.5?
I really think Android would benefit more out of this hardware. It seems as if everything Unix based always requires less resources and gets the job done!
I also would like to know how I can uninstall these game demos that are eating up space? Will this be a registry edit?
I feel as if Android would FLY on this device. WM6.5 is getting the job done, but it's to late for Microsoft with me. I've used Linux for some time and I just think it's better. Huge supporter of Linux!
Click to expand...
Click to collapse
oh, no grouches intended (and the "I have a life" excuse is old )
There's no way to install Android on the HD2, currently, that's why you couldn't find on these forums how to uninstall it from the hd2
Game demos were not included in my stock rom, if you're using a customized rom from a carrier, then either you find and delete the relevant files, if that's even possible, or you flash a clean custom rom from the rom dev forums which includes onyl the necessary software... but then again, I know all this info because I found it on the forums
ephestione said:
oh, no grouches intended (and the "I have a life" excuse is old )
There's no way to install Android on the HD2, currently, that's why you couldn't find on these forums how to uninstall it from the hd2
Game demos were not included in my stock rom, if you're using a customized rom from a carrier, then either you find and delete the relevant files, if that's even possible, or you flash a clean custom rom from the rom dev forums which includes onyl the necessary software... but then again, I know all this info because I found it on the forums
Click to expand...
Click to collapse
Look at you, browsing through forums and stuff. When I grow up, I wanna be just like you.
Thanks for the info. I do have a custom ROM from TMOUS. Has games like guitar hero, prince of persia...more bloated ware. I estimate about 30 mbps of used space.
Devils1stBorn said:
Look at you, browsing through forums and stuff. When I grow up, I wanna be just like you.
Thanks for the info. I do have a custom ROM from TMOUS. Has games like guitar hero, prince of persia...more bloated ware. I estimate about 30 mbps of used space.
Click to expand...
Click to collapse
If they allow you to uninstall the games this is how you would go about it:
Go to the settings tab in Sense -> menu(lower right corner) -> all settings -> system -> remove programs.
Now the other option would be to flash your current rom to something faster and less bloated. T-Mobile US Rom Development Forum
I definitely recommend you read the Stickies before going about flashing your phone. If you have any questions don't hesitate to ask! Would suck if you brick your new HD2 just because you didn't! This is what these forums are for despite what some members might claim.
As for your other questions yes Android is Unix based and is probably going to be available for the HD2 sometime in the future(don't ask when). There's already a dual boot app so when Android becomes available switching between the two operating systems should be a breeze.
Welcome to the forums and enjoy your new phone!
Hi,
A bit irrrelevant to reply here, but I did not any other place. Have been following this forum for quite sometime. Been around with windows mobile app development for sometime. But what really interest me is when people from this forum tweaks Rom image or port to other harware. Here things look quite easy. Is it really easy? I saw one single person tweaking a ROM image and porting to different hardware?
Hope I have not offended anyone.
- Herojit
Toss3 said:
If they allow you to uninstall the games this is how you would go about it:
Go to the settings tab in Sense -> menu(lower right corner) -> all settings -> system -> remove programs.
Now the other option would be to flash your current rom to something faster and less bloated.
I definitely recommend you read the Stickies before going about flashing your phone. If you have any questions don't hesitate to ask! Would suck if you brick your new HD2 just because you didn't! This is what these forums are for despite what some members might claim.
As for your other questions yes Android is Unix based and is probably going to be available for the HD2 sometime in the future(don't ask when). There's already a dual boot app so when Android becomes available switching between the two operating systems should be a breeze.
Welcome to the forums and enjoy your new phone!
Click to expand...
Click to collapse
Thanks. And no, it only allows me to uninstall apps I've installed after the initial setup. I've been through system files and the sorts and I can only find icons and other "blah" that's not the actual install directory. I show all the hidden files and still, can't find it.
Yeah, I'm looking forward to Android. Don't need the dual boot. Just a solid port with solid drivers.
Sorry everyone for the irrelevant post again.
I was hoping that someone will reply saying - "porting ROM is not a big deal, this is how you do it"
- Herojit
herojits said:
Sorry everyone for the irrelevant post again.
I was hoping that someone will reply saying - "porting ROM is not a big deal, this is how you do it"
- Herojit
Click to expand...
Click to collapse
Say what?
What's with your post?
OP. I'll port Android on HD2 for you for $50. You gotta send me your phone tho.
I am a tek savy guy too. I fix microwaves!
FloatHeavy said:
OP. I'll port Android on HD2 for you for $50. You gotta send me your phone tho.
I am a tek savy guy too. I fix microwaves!
Click to expand...
Click to collapse
Epic fail.
one thing that has been alittle pain is how the albums are viewed. i created an album for videos, yet when i view I can't have a name of the file visable, just a thumbnail. that doesn't work well at all. works fine with pictures cuz what you see is what you. videos start with a black screen; becomes a guessing game. am i missing something?
Heyho fellas!
As this is my second post.. and first thread.. I would like to take a second to introduce myself a bit
As my nick states I call myself "Puenos", and after visiting this place for quite a while, I've finally decided to register here too!
Enough chitchat, here's my [Q]:
______________________________
I've recently read quite a lot about ppl asking for a port of WinMo for Android..and after some reading I realised something..
Besides those simple answers asking ppl WHY somebody would want that, most arguments where about how legit it was.. Because WinMo is closed source..
Well... I'm no dev or anything like that.. I'm simple wondering about a few ppl, their ideas and find myself thinking about something abstract myself.. sooo...
QUESTION:
What do you think about ports of
Basilisk II - an Open Source 68k Macintosh emulator
--> There's even a port for Sony PSP and it's quite fun to use it
and before you ask..
AFAIK! Apple provides downloads for the old classic system discs without any charges legally! (correct me if I'm wrong pls..)
Link would be basilisk.cebix.net/
Maemo/MeeGo - an open source, Linux project
-->As Nokia is about to lauch their first MeeGo-Device I would believe it's quite an interesting idea
Link would be meego.com/about
Windows Mobile/Windows Mobile 7
--> Yeahyeah, I know.. closed source and well.. but there are already some Windows Mobile emus on the net I believe? Some even written in Java?
So there would exist a possibility to optimize Android's Java-Engine.. I mean.. the apps converting Java-files to Android-APK for more convient use so it would be possible to port some Java-emus?
I couldn't find the link to the Java-emulator now.. but by searching, I found this:
Link: downloadsquad.com/2008/03/02/microsoft-device-emulator-lets-you-run-windows-mobile-6-on-your/
So there seems to be an application for Windows to be called "Microsoft Device Emulator" which let's you test WinMo-Apps on your PC by emulating a WinMo-Device! Microsoft also seems to provide some ROM-Image to use for this Device Emulator as seen here:
Link: microsoft.com/downloads/details.aspx?FamilyID=38c46aa8-1dd7-426f-a913-4f370a65a582&DisplayLang=en
Again.. I know WinMo is not open source.. but as Microsoft seems to provide those ROMs.. I wonder if it's legit to use those ROMs to test a self-written or ported emulator for e.g. Android?
x86
Uh... there was a port of Bochs/Qemu for Android some while ago.. but the "port" was rather a proof of concept I think?
There was not much for me to do, using this port I got the same error messages I got using Dosbox, which I thought where problems due to usage of the DOS-environment..which I hoped to escape using this "Bochs/Qemu"-port..
But there's also a Java-emu for x86 architecture...called JPC!
More some kind of proof of concept too, but really interesting! At least for me!
But I somehow don't get along with FreeDOS...and can't seem to boot DSL, even though the applet on their website showed it working... but oh well..
Also, I was wondering if it's possible to run more Linux distros on Android using Bochs/Qemu.. but can't seem to get it to work by now...
Maybe it's just my fault :/
Bochs/Qemu for Android: forum.xda-developers.com/showthread.php?t=692682
JPC- Java x86 VM: jpc.sourceforge.net/home_home.html
__________________________________________________
Well... that are my 0.02$.. Again.. I'm not a dev..nor do I have the massive knowledge other ppl have here.. Just thought I share some ideas and hope some ppl might find themself interested in working on something.. not necessaryly ports, stable emus are enough work I believe.. But yeah.. here you go!
Oh and well.. just for the people asking "why would you want that? WinMo/Linux/Whoeva is fo da **** 'n Android is da best, yo!" who seem to be present here..
Why not? This place is called "xda-DEVELOPERS" Why joining a website/community when you're not interested in changing/experimenting?
I believe that some people here should be more open to various things.. If you don't want to change a thing on your device.. why going through the effort even reading some topics here or buy such a versatile phone? Just use your old Nokia and play "snake" and call ppl &write messages!
____
Uh and yeah.. I'm sorry if I did anything wrong.. used "search" and most infos are from this pages.. so I don't really think I've digged something old closed up again... and yeah.. links.. are not links without permission I do not have (new user and such ;3) but I hope the linked pages are alright to be linked.. if not.. I'm sorry guys
______
So... I'm interested in your opinion! What do you guys think?
Hi, I am working on a new site with some of my buds...
Since we all have HD2's lol we will start here. The plan for this site is to help you with your android hacking. Like I said we will start with the HD2 for right now but eventually expand a whole lot. We want to have Android latest news and phones, help the community out. Maybe have forums eventually for other android devices in the future. Who knows where this idea will take us, but we want to focus on helping out the community. In no way we will be competing with XDA, but for Newbies is not easy reading thru all these phorums; or they are just lazy lol. We currently have a writer, graphic designer and a Mod freak to start things off. We want to know what you guys think, feel free to discuss and overall: What would you like to see on the site?
The site shall be called WWW.ANDROID4LIFE.COM and it goes live real on 3-1-11
You can preview the site now! Here: http://www.wix.com/casademipadre777/android4life
Leave comments/questions/concerns/feedback/ ++++++
Thank you!
Very good site. Fantastic for beginners. Layout is easy to see and format throughout is good. Continuity also good.
One thing I will mention is that the transition effects between pages may be a burden for some older legacy computers and people running a a poor connection. Perhaps having a feature to avoid this would be good.
Good work man
lukey-windy said:
Very good site. Fantastic for beginners. Layout is easy to see and format throughout is good. Continuity also good.
One thing I will mention is that the transition effects between pages may be a burden for some older legacy computers and people running a a poor connection. Perhaps having a feature to avoid this would be good.
Good work man
Click to expand...
Click to collapse
Thanks. I'm glad you like the concept, and you are right... Pure Html sites are better but they lack on data stability, which is why we are using more flash sites. Besides they are more simple and I am a flash freek lol. This site is more for our generation and you need a good internet connection jaja! But we do have a link to update your browser flash player, we hope that helps some people. I really appreciate your feedback and trust me your suggestion is kept
it appears like its a NAND flashing method you are building here
you should specify that, as we know the other method is via SDCard in Winmo 6.5
also you should highlight the importance of the very basic and foremost first step of all
flashing HSPL3 (2.08HSPL)
then, MAGLDR
then everything else follows.
just my polite suggestion, very nice website BTW
jigners said:
it appears like its a NAND flashing method you are building here
you should specify that, as we know the other method is via SDCard in Winmo 6.5
also you should highlight the importance of the very basic and foremost first step of all
flashing HSPL3 (2.08HSPL)
then, MAGLDR
then everything else follows.
just my polite suggestion, very nice website BTW
Click to expand...
Click to collapse
Thanks jigners, we are thinking of adding a seperate tab for the SD Method for those that follow. But you got it right we are Emphasizing the Nand method. We will talk about this in the Video Tutorials along with all these major important steps, thanks!
Asshhhh.
Oeh, ok i try start at first things. It will be hard for you to understand but i give my best.
Never ever dont think this way - i have new and good pc (laptop, tab or smartphone) and my friends have too. So i create website, fun yes.
Real life is other. 65% people use older pc-s. Even more, think if someone goes to this site with hd2 and winmo, what and how he then see this page. This ugly and today outstanding flash IS NOT good way make good website. I'm serious.
REMAKE IT NOW.
About design.
I liked it. Littlebit mottled but not hurt everyone.
Site visitors counter today also out. Just place it bottom and hide for itself only.
I recommend to you get better some php based cms and attach your design. Then your site will be gotten on fly. With hd2 winmo and 3G. As you want bring beginners to site.
And one hint more. Think again about site content and main idea. Why? Week ago i seen on HTC site HD2, today not.
I dont want claim or blame you. Just these opinions i got whe i looked to this site. I thinked itself many times that hd2 needs some special site for helping xda devs work better and not waste time for threads named like these examples just gotted at this forum: [Q]Help needed Please, problems, HELP!
datas0ft said:
Asshhhh.
Oeh, ok i try start at first things. It will be hard for you to understand but i give my best.
Never ever dont think this way - i have new and good pc (laptop, tab or smartphone) and my friends have too. So i create website, fun yes.
Real life is other. 65% people use older pc-s. Even more, think if someone goes to this site with hd2 and winmo, what and how he then see this page. This ugly and today outstanding flash IS NOT good way make good website. I'm serious.
REMAKE IT NOW.
About design.
I liked it. Littlebit mottled but not hurt everyone.
Site visitors counter today also out. Just place it bottom and hide for itself only.
I recommend to you get better some php based cms and attach your design. Then your site will be gotten on fly. With hd2 winmo and 3G. As you want bring beginners to site.
And one hint more. Think again about site content and main idea. Why? Week ago i seen on HTC site HD2, today not.
I dont want claim or blame you. Just these opinions i got whe i looked to this site. I thinked itself many times that hd2 needs some special site for helping xda devs work better and not waste time for threads named like these examples just gotted at this forum: [Q]Help needed Please, problems, HELP!
Click to expand...
Click to collapse
I understood some and thanks, we will work on making a back up for those that use older pc's lol. Thanks for the tips too, the datat that flash sites produce is awesome. The "visitor counter" feature that you mentioned is built in on the url as soon as you click it, the features of flash sites. We certantly want this to help people and make it easier to see, thanks... I hope we don't become like that site that you mentioned, that just disapeared lol...
Great job guys,
u definitely need to make that site live.
rikardo1979 said:
Great job guys,
u definitely need to make that site live.
Click to expand...
Click to collapse
Yeah it will be! Can't wait, we are going to be adding a lot of stuff.
wanna help?
Well, we need a logo for our site! Anybody want in?
looks good,can't wait till its up.great job
puch77 said:
looks good,can't wait till its up.great job
Click to expand...
Click to collapse
Thanks puch77, gotta love those sevens
Hey is there gonna be a tp2 section
sent from Simple~Mobile G1
dswaggz said:
Hey is there gonna be a tp2 section
sent from Simple~Mobile G1
Click to expand...
Click to collapse
u mean the phone? touch pro 2 ..... hmmm... We don't have one, If I can get one, we could....
site is down!
vyklos said:
site is down!
Click to expand...
Click to collapse
We are not Live yet but you can preview the site here http://www.wix.com/casademipadre777/android4life
!
We have added a tab that in the future will have the G2 hacks!
In "Download" page you put only NAND builds. I think, links to some modern SD builds also must be present on download page.
!
and_p said:
In "Download" page you put only NAND builds. I think, links to some modern SD builds also must be present on download page.
Click to expand...
Click to collapse
They will, actually the SD method will have its own support page
Looking good. I would change the background color to android green . +1 on a non-flash link site.
It seems there isn't a lot of activity around the Arc yet, so I am going to attempt to learn how to cook SE Xperia ROMs, from scratch :-S
I would appreciate pointers to the best tutorials and software (it will speed up the process); I am a very quick learner so I hope to be able to contribute something to XDA Devs, even if it comes out half-baked!.
Wish me luck...(gulp!)
Nice i also was planning to work on android roms (just for fun) I'm a fulltime Linux user so i know my way around Linux systems. But nice to hear some others also intrested.
here is a handy tutorial to start
http://forum.xda-developers.com/showthread.php?t=775505
http://forum.xda-developers.com/showthread.php?t=704561
I know there was a thread with unix scripts i can't fin it anymore, lost it forever
Sounds good. I think the first thing we need though is a recovery with nandroid, makes testing experimental roms (ie, ones I made made myself which likely wont work) a lot safer!
I would take linux courses just for that, I hope one day we will have courses for Android dev.!
Till then I love to mod the look of statusbar,icons,lockscreen and camera. I just have to change the appropriate png pic and edit some xml files
vegetaleb said:
I would take linux courses just for that, I hope one day we will have courses for Android dev.!
Till then I love to mod the look of statusbar,icons,lockscreen and camera. I just have to change the appropriate png pic and edit some xml files
Click to expand...
Click to collapse
It's not hard to learn Linux. Just start using it fulltime and get familier with the terminal. I never followed a Linux course and now i'm now my way around. I ahve ubuntu servers and using ubuntu fulltime (for 4 years) now it's easy to use ubuntu because you can do everything from the GUI.
I write about Linux and read/follow sites related to Linux.
If you don't use it it's hard to learn just try to install dualboot and try using fulltime Linux. You will have problems like something isn't working well fixing the issue will help you learn stuff
cool
thanks for the links, I shall read them later. I will have to get a linux system running, I'm assuming I can duel boot it on a laptop...time to google...
thintin said:
thanks for the links, I shall read them later. I will have to get a linux system running, I'm assuming I can duel boot it on a laptop...time to google...
Click to expand...
Click to collapse
It is possible and easy with ubuntu.
Hi
I am a cooker of WM Rom and now i have SE Arc
I already run the dualboot ubuntu\W7 in my Pc
I am very happy to see this thread, because at the moment are new to Linux
I started to know the kitchen for Android and I must say that it is very fun to work
I will be happy to learn and to help in the limit of my knowledge ...
best regards
alesscam said:
Hi
I am a cooker of WM Rom and now i have SE Arc
I already run the dualboot ubuntu\W7 in my Pc
I am very happy to see this thread, because at the moment are new to Linux
I started to know the kitchen for Android and I must say that it is very fun to work
I will be happy to learn and to help in the limit of my knowledge ...
best regards
Click to expand...
Click to collapse
Welcome to the Android world
I also did some ROM cooking for my X1 but this is a little bit different and you have more freedom making changes to the ROM that's why i love Linux.
I people have problems with Linux they can always pm me i will do my best to help you learn it.
Sent from my LT15a using XDA App
Hi I am new to Android SDK, I know a little like creating an android project, android project structure, compiling it & testing it on a phone, but I do not understand anything in the source code. So I need to start from the basics, is this tutorial good for basics ?
http://www.cbtnuggets.com/series/219
Have a look at the official developers guides: http://d.android.com/guide/index.html
Theres really a lot of helpful guides that should teach you (almost) all basics you need to code on android.
Why should I not learn this first ?
http://www.cbtnuggets.com/series/219
Springles said:
Why should I not learn this first ?
http://www.cbtnuggets.com/series/219
Click to expand...
Click to collapse
Oh sorry, I didn't notice the topic list further down the page. If you really have no knowledge of (object-oriantated) programming some tutorial like this would indeed be a good idea. About this one I can't tell you if this will help you, since its paid content. Looking at the topic you will get all basics you need for starting with the link i wrote above. (Also theres some videos you won't ever need using the Android SDK)
IMHO: I would not pay that much money for video tutorials without excactly knowing its worth it! (Independent reviews!)
Theres a lot of free tutorials explaining the java basics out there, if you're not in hurry I would rather read some of those. (I sadly only know some in my native language)
Well I am in a hurry, ill watch it on my friend's laptop, hehe.
Springles said:
Well I am in a hurry, ill watch it on my friend's laptop, hehe.
Click to expand...
Click to collapse
In that case I would at least have a look at local courses that you could take since its always better if you can ask back for an explaination if you don't understand something. (And if you are new to programming I'm pretty sure this will happen )
Forsaken said:
(Also theres some videos you won't ever need using the Android SDK))
Click to expand...
Click to collapse
Can you tell me which video chapter's are not needed to learn ? http://www.cbtnuggets.com/series/219
1-19 and 28+29 should be everything you need to understand how to use the android sdk. 12 & 18 (swing) is also different on android (afaik its not swing there) even it's quite simlar to it, so depending on how specific those videos are they might be a help anyway.
Can you tell me what is the equavelent package for:
java.awt & javax.swing for android ?
Springles said:
Can you tell me what is the equavelent package for:
java.awt & javax.swing for android ?
Click to expand...
Click to collapse
There is no equivalent package, as the graphical interface is completly different. I will suggest you take a look to developer.android.com under the section of activity and view:
http://developer.android.com/guide/topics/fundamentals/activities.html
http://developer.android.com/guide/topics/ui/index.html