This app helps you keep track of how you feel and lets you see when stress and anxiety are becoming a problem. It’s simple, you move the mouth of a cartoon face up and down to represent how you really feel. You can then write a brief description of what’s happening and if you want to, you can list all the feelings and emotions you’re experiencing.

Moodnotes app

You can quickly identify trends, as you may not realise how many bad days you're having. 

It may sound negative, but I think it's a great way to identify potential problems. A lot of people will probably overlook this app, given its price and the fact you could note it all in a journal, but I’m sure you’ll find it a very effective personal development tool.