The term APK refers specifically to Android application packages. This means that if you are using a Xiaomi device, you can easily install third-party sticker apps that aren't always available on the official Google Play Store. These apps often host a wider variety of animated or "hot" stickers. However, iPhone users cannot use APK files directly. To get these stickers on an iPhone, you typically need to receive them from an Android friend or use a cross-platform sticker maker app available on the App Store.
Para conseguir stickers con movimiento en tu iPhone, no puedes instalar archivos APK (como en Xiaomi o Android), ya que iOS solo permite aplicaciones desde la Stickers con Movimiento para WhatsApp: Guía para Xiaomi