What are some alternatives?
When comparing A-Painter and Tilt Brush by Google, you can also consider the following products
SprayPrinter - Convert digital designs into wall art from your smartphone
Snap Art - Snap's augmented reality platform
MasterpieceVR - Powerful VR sculpting & painting tool
Oculus Medium - Sculpt, model and paint in virtual reality on a 3D canvas.
VR Sketch - A tool for designers to draw inside virtual reality
AI Painter - Turn your photos into paintings