WhatNext: Automatic to-do list app

I've always struggled with distractions, finding myself swamped in a pile of tasks that never get done. I didn't know how to prioritize. I have lots of ideas, some great, some good, mostly terrible! But, they were constantly swimming around in my head, taking away focus from what I really needed to do. I'm an engineer, I have multiple projects running simultaneously and I need to constantly context switch. Also, I work from home so I have personal chores to do and no fixed working hours. I found most todo list apps didn't quite work for me for a couple of reasons. First, I don't like to do too much planning. The majority of apps required me to schedule tasks on a particular day and choose morning, during the afternoon, or in the evening. Some even required exact time and duration. That's not how I live my life and is also not what the majority of tasks I work on required. I'm a problem solver, thinker and engineer. Most of the time I've never done the task before, so I don't know how long things are going to take. Second, I found myself in a cycle of: Create a list of to-dos for the day. Choose something to work on now. Finish that task then go back to my list to decide what to work on next. Repeat until exhausted. Then if I didn't complete the list for that day, I would have to move the unfinished to-dos to the next day. Very demoralizing. I didn't want to schedule tasks. I didn't want to keep having to look at my todo list to decide which task to do next. So how should I decide what to work on next? How to easily prioritize tasks is quite simple. Choose two parameters per task and order them based on how much time I have available. Those parameters are size and urgency. This is not a new concept, it's been around for a while and many people already use this method successfully.