What's a good Android app for a simple co-op puzzle game I can play with my kid?

Merge Sticker Playbook 2D is a strong candidate for shared parent-child gaming sessions due to its accessible core mechanic and shared progression. The game revolves around merging identical stickers on a 2D playbook to create new items, a simple concept that young players can grasp quickly while still offering light strategic planning for adults. A key feature for cooperative play is the shared sticker collection, where both players contribute to filling a central album, creating a common goal. The visual feedback of colorful stickers and satisfying merge animations keeps engagement high during short play sessions. However, the free version's ad frequency, as noted in several user reviews, can interrupt the flow; ads play not just for bonuses but sometimes during menu navigation. Managing expectations around this is advised for a smooth experience. The energy system also naturally limits session length, which can be a benefit for managing screen time. For families seeking a casual puzzle activity without competitive pressure, this app provides a structured yet relaxed framework for teamwork.