For Android, I've been using DroidEdit and DroidScript (and DroidScript lets you compile Javascript to an apk, without the hassle of setting up Cordova).<p>I also have Bit Web Server for php.<p>I haven't found a good option for Javascript console debugging on Android. (not linking to your PC to debug like Chrome does, I mean using the JS console on my phone)<p>My problem is the lack of a clip-on physical keyboard. I'm looking for a clip-on keyboard like the way the Moga controller clips on to my phone. The iControlpad2 would have been nice, but that project turned out to be a fraud. I have a qqtech mini bluetooth keyboard, but without a clip-on capability it's hard to use on the subway.<p>I saw clip-on keyboards that work only with my phone (Samsung Galaxy S4), but that's no good because I'm upgrading soon.
There is QPython on Android that is ok. What I found frustrating with Android is that the python implementation of QPython is restricted to QPython. For example, I can't access to the Python REPL from emacs on my tablet. I saw some SSH clients for android (for example: Juice SSH). I am tempted to set up SSH on my computer and ssh there from my tablet, so I can have access to my whole environment from Android; the only problem with that is that it depends too much on having access to Internet.
For Python on iOS you should try Pythonista[0]. It's $7 and it's really good. I use it on my phone more often than my iPad but it runs great on both.<p>[0]: <a href="http://omz-software.com/pythonista/" rel="nofollow">http://omz-software.com/pythonista/</a>