Your 3D model may feel slow or unresponsive (often described as "hard") on a tablet usually due to tablet hardware limitations, high model complexity, or unoptimized files.
Tablets have less powerful CPUs/GPUs than desktops, so models with too many polygons, large uncompressed textures, or no level-of-detail (LOD) layers strain the device’s ability to render smoothly. Unsupported file formats (like heavy .fbx files) or outdated 3D apps can also cause lag.
Try simplifying the model by reducing its polygon count, compressing textures, or using a tablet-optimized viewer (e.g., Sketchfab Mobile) to improve performance.