With Homey v2.1.2 and Android app 2.2.1.299 its also with me very often that the connection to my Homey is lost. Trying to edit a Flow is a nightmare, very very long waiting times.
Phone is a Fairphone 2 with Android 7.1.2
I have also an iOS Tablet (iPad Pro), seems to have better performance using the App but also on that App the deley’s are long when loading a flow for editing.