I have been using KeePassX for many years and couldn't find the suitable app for my mobile device.
I have found this with KeePassDroid for my Android Nexus 4.The new Dropbox Android app plays nicely with KeePassDroid. I use Dropbox to synchronize my keepass database, because it is available on all of the platforms I use daily: Mac OS X and Android.
It's very easy to use.
I install it on my desktop first, and move my keepass database into my dropbox.
Then, fire up the Dropbox Android app, and log in:
Navigate to your database and click on it:
It will jump to the password screen in KeePassDroid:
In the background the Dropbox app will be waiting to see if you make changes to the database. If you do, it will upload your changes back to your Dropbox. Now you can save and make changes to the database on your desktop, it will sync to the Dropbox and will instantly make changes to your Android later.