I think it would be a great idea to be able to track feelings, health and mood.

Yazio has this feature but I don't like their app. It is very helpful when you know you haven't slept well, are unwell or dehydrated and your weight has moved accordingly without any excessive change to diet. Especially helpful for women at all stages with hormonal fluctuations.

Mood tracker. You should be able to link mood to food. Your mental state is hormonal, wich you can influence with food or training. For example, mood swings and going in keto.
If you can give a rate to everyday, after a month you can see what happens and you can start relating, and make adjustments.

It’d be great to have a feature where I could log my mood and make notes about who I felt after each meal or activity.
That way I could look back and make adjustments and see how I felt might have affected what I ate and vice versa.

Yeah, that will be really great and useful.
I've made a small example for this one: https://imgur.com/a/o49Hi3i

I would love the app to have a mood tracker!

It would be nice to have a place where we could write how we feel at a certain time of the day, in order to see if there is something we do not tolerate. For example, I sometimes feel bloated and it would be nice to be able to note that somewhere to then analyse.
Maybe also see how certain foods impact our feeling of 'fullness' or our mood.

In the morning, and after the main meals (lunch, midday, before bed) a reminder/hint appears in the dairy, where it asks you how was your day (in terms of emotion, health-wise) you are shown emoticons reflecting a range from (0, 1, 2, 3, 4, 5, 6) where the lowest value is very bad, with a frowned/possible angry emoticon and the highest value being a green and laughing smiley face, the middle values are yellow ones.

The essential part of this feature, is that it tracks your mood, sends you hints of improving your fatique, tired or emotional state by adding more veggies or specific items suggestions. You could see a week/month stats graph, that allows you to find trends in your mood and maybe the cause.

Adding the ability to write a note when asked of mood, allowing you simply write "Tired from work" or "Feeling sickly", giving some context to your choices.

Asked in the morning and two other times per day, allowing more frequent mood checks, you could start out a day feeling dead in the water, but end the day on a high note, pulsing with good health.

An simply way of showing mood trends, would be to give an report after a week or month, showing which time of day you are feeling down/good and showing some of the notes and the ability to view full mood history.

I would like to have a way to track more things or categories per day and look at it in my diary and compare to calories, workout etc.

Such as periods, sickness, headache, happiness, drinking alcohol, not eating dairy compared to eating dairy etc.
I would prefer if I could set the categories by my self and choose between emojìs, numeric and a fix number of options of text on each day.

I think it would be easier to see when you look at a longer period of time and it would be helpful to se what happens with your foodplan during a month in different situations.
My idea is that I want it to be similar to in "body statistics" where you can set your own measurement and see it in the over view- but this would be shown in your "lifestyle" instead.
And it would be neat if you could choose what categories to see under lifestyle

King regards Bente