This is my personal favorite and the only one I ever used consistently. I used it while I had an Android phone and looked it up online
T2 Mood Tracker | t2health

Reasons I liked it:

It's very customizable. You can add or delete symptoms to track and create different categories. You can also create your own symptoms and symptom range. Some apps irk me because they'll ask me to rate something like "happy" or "sad" as opposite where for me I'd rather rate how I feel on a scale between content and frustrated.

You can rate your moods multiple times a day and the graphs will show micro and macro readings. Plus I changed the colors and thought the charts were cool looking.

My absolute favorite part of all is that there are no emoticons and it has the most neutral color coding and fonts I've ever seen on a mood tracker. I know emoticons are a part of modern life and I appreciate their use in texting and places like this but on my mood tracker I find them annoying and it reminds me of being given children's coloring books in the mental hospital.