Some days ago I found this app in Google Store and I tried to play.
First, you need to agree with some settings (Privacy Policy, you are 15 years old and they can use your dates).
Now you can choose you Game mode. I think a lot of users are playing Classic when for a win you need to do the best score in just 2 min.
For a Solo Run game mode your screen will load for few seconds.
After all this steps...let's play. I didn't know how to play in first game but the next I had a better score.
I found on reddit someone who claim he knows how to achieve a big score:
"My secret is: be the first to get to get to a park and consume the whole thing and any other holes there. Once done, I go straight to the other park, swallowing any holes on my way. I ignore all the other items until I've consumed both parks, that way I've taken most of the items that give you the quickest growth away from the other holes. Once I've eaten both parks I can swallow entire building complexes without slowing. The key now is to maintain serial killer status and of course, eat all the things."
(Source: https://www.reddit.com/r/gaming/comments/8svkf4/can_anyone_beat_my_holeio_score/)