While there are plenty of task apps out there for the iPhone, it’s not much of a reminder if you don’t remember to run the app on a regular basis to read what you need to do. The most effective method for me is to put it directly on the lock screen of the phone. How many times do you check your phone throughout the day and have to unlock the device? You will constantly see your list without having to run an app.
I take down the notes in Notes, save a screen shot, go to Photos and set the new screen as the wallpaper, and resize to fill screen.