3× 3rd Party Apps
This is a Mac OS app which sits in your menu bar and displays your balance. It can notify you when you make a sale and supports multiple accounts.
nWallet is an Android app which shows your balance, earnings, sales, and comments. It can also notify you of changes to the above mentioned things.
This is iOS only and is arguably the most complete of the three. It works on iPhone and iPad, does everything the previous two examples do, plus it also allows you to browse the Envato Marketplaces.