We recommend the following free apps:
Jour. It allows multiple types of journaling. For example, at the end of each day we recommend writing down good things that happened.
Woebot. Woebot chatbot might be able to help if you have anxiety or depression. It is built by psychologists that worked at Stanford for over 10 years.
We also recommend this guide by the cofounder of Twitch: Feeling Good: Justin’s Program.