Bad memories and no fan for lots of typing, EC Todo is a very simple todo list app for myself and people like me. 
We are not fancy enough to have huge projects with many many tasks to trace, we tried so many todo list apps paid or free, all too complicated and not intuitive enough for solo users.

For us, a useful todo list app should:

[A] Super Quick to create reminders: 

In EC Todo, to create a quick todo-reminder, just 3D touch a color and pick an emoji. Just 2 taps on the screen, here is our new reminder. At most time, see the color-cataloged emoji our brain will naturally recall the content of the reminder. This mechanism can also improve our memory.

[B] Super Intuitive to check all reminders: 

Once open EC Todo, all todo-reminders are cataloged into four colored tiles. Number on the tile indicates how many reminders in this color-group while emojis listed hints for each reminder. So with one glance, we know what to do. EC Todo also features 3D Touch quick widget, Today widget and WatchOS app so we can check our reminders without actually open the app.

[C] Details, maybe:

In EC Todo, each reminder can have a text memo, up to 4 photos attachments and up to 3 alarm notifications. We can edit and update our reminders any time.

[D] Archiveed old reminders:

In EC Todo, checked and deleted reminders are auto archived. We can review old reminders and when need, re-initiate old reminders to live.

[E] Sync between devices:
In EC Todo, we can sign in with FB account, so devices can share the same todo list with one account.

EC Todo is free with ADs in it, if don’t care the ADs, you can remove them via IAP.