Just want to take your guy's opinion - at least those who are into developing websites or web apps.
What would your testing checklist be, as far as browsers and systems are concerned, for a mobile website?

I usually do desktop websites, and test them on IE8+ (8 is the oldest I support). Since I develop on Firefox and Chrome alternatively, I don't need much testing for these, but I would test them quickly. I've noticed the latest Safari to be odd sometimes, so I would try, if possible, to test it on that too.

All is well in the desktop world.

Since I've started doing responsive designs, I've usually tested them on iPhone and iPad. But now I'm doing something a little more advanced, and need to test it more throughly. There are countless combinations of Android systems out there, and also, Blackberries, let's not forget (although not as popular as they used to be).

So, what should I test it on, and what browser/system combinations should I concentrate on, for the non-iOS mobile clients? For desktop testing, my decisions were based on usage statistics. I have yet to see if such statistics can be found for mobile, but I feel that it will be more complex.

And, generally, what would (roughly) be a good compatibility testing checklist?
aliessayli2 wrotehttp://www.mobilephoneemulator.com/

This may come in handy , but I don't think it's accurate 100%
Yes, that's a cool website but it does not test on real mobile browsers, just shows a small frame inside your browser to see what your site will look like.
That's cool, but what I need is to run the website on different mobile browsers to see is it triggers some bug in the browser or looks different for some reason. Browser compatibility has done good progress in the last decade but is still not 100%.

So I want to test in virtual machines or on the real devices and running the real browser software. The question is, what devices and software should I test, because I can't test them all! I am already testing on Windows (desktop), with the browsers previously listed, and on Safari for iOS.

I can use browserstack to test on emulated devices. They are expensive but give you a 30 minute free trial, and with some basic cheating, you can have enough of it. But they have many choices, and I don't know on which one I should concentrate, and which ones I should ignore because they're too rare or obsolete.
he question is, what devices and software should I test, because I can't test them all!
Regarding android there are various designs and screen dimensions so basically you pick a device from each dimension pool.
For example the galaxy s III 720*1280 would be the mobile phone version and the nexus 7 1280*800 would be the tablet version (android versions also vary)
plus on every android there's also a chrome and a Firefox you should check.

browserstack seems to be very helpful but I think having physical devices and testing in real time is better than the laggy virtual machines.

Edit : You can use Adobe Edge Inspect for Synchronized browsing between your pc and phone when building the websites

http://html.adobe.com/edge/inspect/
Firefox's responsive design mode is really good to check how your site scales up on different screen sizes. Avoids you having to load it on lots of different mobile devices to see how it scales.
aliessayli2 wrote browserstack seems to be very helpful but I think having physical devices and testing in real time is better than the laggy virtual machines.
I don't have any android device!
aliessayli2 wrote Edit : You can use Adobe Edge Inspect for Synchronized browsing between your pc and phone when building the websites

http://html.adobe.com/edge/inspect/
Thanks for the tip! Non-free :(
ramiraz wroteYou can use Chrome's mobile emulation. Very useful, I use it all the time.
alex.daoud wroteFirefox's responsive design mode is really good to check how your site scales up on different screen sizes. Avoids you having to load it on lots of different mobile devices to see how it scales.
Thanks. I already use Chrome's emulation mode. It is useful. I didn't know about the Firefox equivalent yet.

My concern is about testing websites on the browser and mobile devices itself for bugs and rendering quirks, which will not appear in any emulation mode.
NuclearVision wroteIsn't there detect screen resolution function in php?
What? I think you are referring to the screen resolution being included in the User agent string. It is not very reliable, though, and will not indicate the size of the window when the user resizes it. It can be useful (thanks), but I don't need it because I'm doing that through JavaScript and media queries anyway.
So basically this could be reduced to:

What are the most popular (in other words most widespread or most used) android OS versions and what are the most used android devices, in your opinions?

And some more questions if you can answer: Should I do some testing for Blackberry devices? Or is it not worth it because they're too rare? And if yes, what devices? Are there other popular devices I should be concerned with (I'm already testing iOS)?

I need to know so that I can test the website on them.