I have had a play with this app this weekend to review how good it will be for our ks1 learners - particularly a child on my class who needs resources to support with his independent learning.
There are four areas that you can explore that support basic number skills. If you get an answer wrong, the incorrect number becomes dull so that you don't press it again. There are 4 questions for each level. One thing that would make it easier for some children would be the option to hear each question.
When you play the more/less activities, there is a nice model that allows children to count cows to find one more. Showing one less is not so obvious as it looks the same as below, but with the cow on the left faded for one less than 2. It might be clearer just to have a line through one.
This will certainly be a useful app for our earlier learners. I will add the opinion of one of our little beta testers tomorrow! Thank you for the trial @urbrainy!