A question to Android-experts:

I checked with the Stagefright Detector whether my Android devices are affected by that vulnerability which is everywhere in the news now it seems.

It seems all our Android phones are safe (e.g. the Samsung Galaxy Trend Plus which I updated myselt with Cyanogenmod Android 5.1.1 some time ago), but my old ASUS Transformer TF101 tablet is vulnerable (running Android 4.4.4 by Timduru (KatKiss)). Not sure if the vulnerability is that important on it as it doesn't have a SIM (no MMS messages), but I guess the malware could come from some web page though.

I checked Timduru's pages and apparently there are newer Android 5.x and even 6.x for TF101 available from him, but my question is:

Will I lose backwards compatibility to some old Android games bought from e.g. HumbleBundles, if I update to a much newer Android version (e.g. 6.x)?

I googled for this and there have certainly been discussions about this, but the linked discussions were ancient from times when they discussed whether Android 1.x applications will work also on Android 2.x versions etc. I got the impression that new Android versions add new functionality on top of old Androids, so the backwards compatibility should be good generally? Is it so?

Hmmm, maybe I will then keep that tablet on Android 4.4.4 for as long as it lives. Too bad, I'll just need to check how to avoid that Stagefright vulnerability. The Detector homepage mainly mentioned about disabling autoloading of MMS etc., which are not relevant for this WiFi-only tablet I think, but I read elsewhere the vulnerability might come also from a web page or through email.

One thing though, my main interest is to keep the (DRM-free) Android games bought from HumbleBundles running on that tablet. I haven't bought any games from GooglePlay or Amazon etc. Not sure if GooglePlay will flat out refuse to install/run some application just because you have a wrong Android version?

If no better suggestions come, I will mark your answer as the solution.

The Play store definitely does a little checking to see if your device is compatible, so you can't install apps that require a later version of Android and/or won't work on your device. I don't know if it works the other way 'round though.
And a whole bunch of the Humble Android games never got updated and don't work anymore (for me at least).

Edit: Oh it is (or used to be) possible to download APKs from the Play store, you'd probably be able to circumvent the check that way.

I haven't been affected by Stagefright or any Android vulnerabilities for a long time. But I guess it's your choice to protect yourself against that bug, isn't it the one where MMS videos can manipulate your devices? In any case...

As for Google Play games, yes, Google Play blocks any incompatible devices from downloading an incompatible app. For instance, White Day cannot be downloaded to my Samsung Galaxy Win. You can always circumvent that by using another device or even an Android virtual machine such as Droid4x to download said apps to the virtual machine/other device firsthand then to your main device, but the end case is, your main device cannot install apps directly from Google Play that it says are incompatible with your device. The same can be said of Amazon. You have to work around such limitations.

This could differ for a plethora of reasons, the most powerful of which is maybe you have the wrong Android version. If the app demands Lollipop and you have KitKat, know that your KitKat Android device will never run said app. However other reasons include selective devices being picked for said app or you have unsatisfactory specs, etc. In any case, installation of such unsupported apps come at your own risk, for the apps may either perform poorly or not work at all. Some apps will work regardless, however.

Backing up Google Play games is also easy if you're interested in that. Just obtain an app that lets you extract the APKs, find the data and obbs of said games, and move them around. An app may demand an updated Google Play Games app, but think of it such like VCRedist on Windows, it's not some sort of DRM as the games doesn't care which account you play the game with (the account that bought it or another account).

Do you have any other Android questions you need answered?

Probably not. In most cases Google adds features in a way that older apps should still run on newer versions.

The main exceptions would be apps that make use of an API that's been discontinued or that require broken behavior to work. Some of the old apps that were accessing the microsd card in the old way rather than in the new way are no longer able to properly function.

I've upgraded across multiple different revisions of Android and I haven't had any that were broken like that. Occasionally, they'll be unstable on newer versions, but I don't think I've noticed that with games. If you want to be sure, you could try downloading the official Android emulator to your comptuer and see if the apps run properly. Depending upon your hardware that may or may not work well to identify problems you'll have.

One thing to look out for with newer Android; Kit Kat and earlier used the Dalvik VM, while newer Android uses ART (Android Runtime). While ART is mostly backwards compatible, there are instances of incompatibility. I personally ran into Deus Ex: The Fall having issues so bad that Squeenix eventually put a warning on the game (but never changed the compatibility test in Play). It took more than a year, but they did eventually patch it, though it still doesn't work perfectly.

Heh. That clicks in with my mention of Final Fantasy games on Android. They suffered from the same problems as explained above, partly because of the change between Dalvik and ART. It's a good thing that Android apps are still functional and the Play Store as well as the Amazon Appstore and what else have we are still breathing with life, Lollipop and after.

You can download All version and also Premium Android Application from Here. Visit this website.