Compatibility with XB engines is known to be one of the significant features of Chess for Android, the application that we may simply call "the most engine-tester friendly GUI available for Android". After all, as a user focused on nothing but the outcome, CfA has always been the most useful, if not the most beautiful one to me since the day i've been involved in chess on smartphones.
Now, with the new 5.2.2 version, XB engine manangement takes a step further with improved time control abilities. Frankly said, we'll not be limited to "fixed time per move" setting anymore and Fischer (blitz) clocks will start to run between xb engines too.
XB engines (probably most of them) which could not handle so far this most common time control setting are now expected to become compatible thanks to a simple trick, just by sending the clock values to the engines with all commands that require engine thinking.
If you wanna read the discussions and comments about the issue, read the relevant forum thread: HERE.
* Chess for Android 5.2.2 is available at GOOGLE PLAY with the standard version.
* An apk copy can also be downloaded via my repository: HERE
* Wait, it's not over: In case you wanna use the remote controlled PC engines, you may prefer to download the network version: HERE
P.S.: Then what happens with thousands of games already played for Rapidroid? Um, well, this is some kind of complicated situation in which it becomes quite difficult to evaluate all available solutions due to the fact that the frequency of future engines updates may be conflicting... bla bla bla... = I don't know yet what to do but i'll figure out something.