Performance on physical Android device

I have a simple app that displays a grid 15x15 (as a table) using ng-repeat to iterate over rows and a nested ng-repeat to iterate over the cells (drawing data for each cell from a $scope(d) object (as a result of a previous RESTful request (JSON returned in the resolve method within the state.
The performance of this is dreadful on my Nexus 4 - takes a couple of seconds to render - this isn’t counting the data retrieval (as it is coming from a local SQLite db after the first request).
Now this may be a specific angularjs (or Cordova) question - in which case I’ll happily re-post on SE (but didn’t want to x-post initially), but thought I’d try here first given all the performance focus the Ionic folks have been putting into Android recently. Is this something to do with $apply/ $digest cycles that I have read about? I tried using :: in my ng-repeat to prevent binding (I think I got that right in the docs) but that didn’t seem to make much difference (and of course stopped the two-way binding to my inputs (which are in each cell).
I am pretty new to Ionic/ angularjs so any pointers would be gratefully received.