I've looked at a lot of research on this and many experts agree that one of the best ways to keep on track with resolutions or just maintain a good balance in life is to keep a journal. I searched for a smartphone app to make that easy.
Momento is a favorite for people wanting to keep a journal of thoughts, dreams, and everyday activities. Each day you can add journal entries by tapping an icon and begin writing. Add tags, add people you're with, and add photos.
Remembering to journal is the hard part for anyone who wants to get started. Momento helps by adding notifications. Set this up any way you'd like, maybe first thing in the morning or before you go to bed. Set another alert to take a photo at a certain time.
You'll be reminded on your phone and on an Apple Watch if you have one. This alone makes Momento perfect for wanna-be journal keepers.
It also auto-populates your memory feed by connecting to social media accounts.
The downside is, the Momento app is for iPhone only but there are similar apps in the Google Play Store for Android users. Day One is a great choice but it doesn't have social media integration.
Momento is free but a premium version lets you look back beyond one year at your memories.
If you're serious about journaling, one of these apps will help.