If anybody wants to focus on just the design of an app, head over to https://marvelapp.com
Here you can design your app, for free. It has a brilliant drag and drop builder and is pre loaded with navigation menus, app bars, graphs, buttons, etc. It allows you to place items anywhere, and select the specific device that you are building for.
I find this helpful when you have the idea, but don’t want to fiddle around with size in thunkable just yet, until you have your design as close as you can get it to what you want.
A lot of people here probably already use this website, but if you don’t, maybe even consider giving it a look