Read the entire video description for more information. And if you think that this phone is outdated and it's not relevant for you, please just move on with your life... :) I will remove this video if/when this issue is fixed.
From the release of alpha 0.12 (here: 0.12.3) I'm not even able to start the game. The controls broke with the release of 0.9, but now it's even worse. I didn't even mention the graphical error in the menu system because it was quite obvious and is not the big issue here.
The control issue was reported directly. Tommaso @ Mojang confirmed the problem (see further down) and said it would be fixed when control support was integrated.
It has been quite some time since controls were added, and the Xperia PLAY problem has not been fixed. But now that's a small problem compared to crashing the phone completely....
This video was posted on reddit in this thread:
https://www.reddit.com/r/MCPE/comments/3rhcfr/this_is_how_broken_mcpe_is_on_xperia_play_100/
First bug report:
https://www.reddit.com/r/MCPE/comments/2jm1ej/010x_beta_bug_report_thread/clkfzde
Discussion with response from Tommaso:
https://www.reddit.com/r/MCPE/comments/2sx5dv/the_xperia_play_situation/
"You're correct, it will be fixed when gamepad support is added :)"