Don't make separate lists in different apps - that's exactly what's making your phone such a mess. Google Keep actually works fine for this because it's simple and syncs across all your devices, so if you start the list at home and finish it at the supermarket there's no problem. What you should do is keep everything in one place from now on.
That said, there are specific shopping list apps that are a bit more convenient. Todoist is pretty popular, it has a good workflow for checking off items as you go through the supermarket, and you can even organize it by categories (produce, dairy, etc.) if you want. Another one I know a lot of people use is Bring, which is even more minimalist, just for shopping. Some supermarkets also have their own apps where they add deals and stuff, so it's worth checking if Carrefour or Éxito have anything.
Honestly, you'll be fine with Keep. The real trick is that whenever you think of something you need to buy, add it to the app right away, don't wait to do it later because that's when you'll lose it. And before you leave home, check the list once to make sure you didn't forget anything. That works better than any fancy app.