Pineapple tree 5D Magic Letter is a set of creative interactive toys, with 26 solid deformed letters combined with smart devices. It uses augmented reality (AR), artificial intelligence (AI), computer vision (CV) and other technologies, and has *** 10 functional games, among which there are five functional games (experience discovery, picture recognition, parent-child encyclopedia, interactive battle, CV) combined with mobile phone tablet app. There are five ways to play without a mobile phone tablet (deformed letters, professional squares, magnetic spelling, interactive cards, and puzzle chess). Developers have also designed brackets and adapters to free children's hands, so that children can better experience the fun brought by high-tech toys and deeply remember words and encyclopedias. Bololetter is a high-tech children's product for learning English and parent-child interaction.