Counting Sheep: Brain Training is free on App Store

Counting Sheep: Brain Training is a light iOS puzzle game that turns counting into a cognition workout. You keep track of sheep as they walk into a pen, climb down from trucks, move between cottages and choose whether to follow a signpost. It sounds simple, but it gets harder as more sheep move at once.

It suits players who like quick brain teasers, memory and attention challenges, or a relaxed game for short breaks. There are no ads and no subscriptions.

It normally costs $1.99 and is free for now. No end date has been given, so claim it soon. Once you download it, it stays in your App Store purchases, and you can reinstall it later at no cost.