Flutter apps work perfectly fine on my current device, a Redmi Note 4 with Android 7. In order to check compatibility I tested them on my low-end Yoga tablet running Android 4.4.2 and got very bad results.

It seems the app freezes for 2 or 3 seconds and then renders all the changes that happened before. Then it stalls again for 2 to 3 seconds and so on. I tried it with the least complex setting possible, a text field and a button, no animation. So it's not a performance issue. It must be a rendering thing. The performance overlay shows appr. 2000 ms/frame. I also tested it with your example apps like Gallery, and also with the published Newsvoice app. Same results.

I know you don't officially support tablets. But I don't see why it's a problem on these devices. After all, the tablet fulfills all requirements for flutter. If I can't be sure flutter works on most tablets (also low-end) it's difficult to use it in production.

Is this a known problem on certain devices or on specific Android versions? Any suggestions how this can be solved?