I have just released VGB-Android 3.8, a new version of my Nintendo GameBoy emulator, with the Replay feature, letting you record your gameplay and then "go back in time" replaying the recorded gameplay:

https://play.google.com/store/apps/details?id=com.fms.vgb

In order to start recording, select "Record" from the menu or click on the "target" icon in the action bar. The diamond sign will indicate the ongoing recording. To replay, select "Replay" from the menu or click on the "timer" icon in the action bar. The triangle sign will indicate the ongoing replay. You can terminate replay at any moment by pressing a gamepad button.

As the options menu was becoming crowded, I had to rearrange it. The Freeze/Restore functionality is now accessible via a single menu option called "States", which also lets you access online State Exchange. Cheatopedia and Advanced items got their own submenus.

Finally, I added more caching to the File Selector, making it smoother. File Selector now only shows progress dialog when processing large folders.

• Added Record/Replay feature letting you go back in time.
  
• Now only showing File Selector progress dialog for large folders.
  
• Optimized File Selector labels and screenshots for smoother scrolling.
  
• Merged Freeze/Restore into single States dialog.
  
• Collapsed cheat-related items into Cheats submenu.
  
• Collapsed advanced items into Advanced submenu.
  
• Made Enable Cheats and NetPlay menu items checkable.
  
• Fixed NetPlay crash when own IP address can´t be detected.
  
• Added Dragonball Z: Legendary Super Warriors to the Cheatopedia.