Android Box ?

I’m, new to all of this: I’ve purchased 2 Android boxes and in both Kodi upgrades have exceeded the boxes Andriod capabilities. Kodi 17 is calling for Andriod 5.0 (current box has 4.4). I did fall into Kodi by happenstance, but I have grown very fond of the ‘feel’ of it. So which box should I get that will allow me to grow with Kodi?