Bridge will work with the iPhone 6, but performance may suffer for some applications. Standard iPhone VR experiences may be acceptable, though framerate of full mixed reality or positionally-tracked VR may be suboptimal. iPhone 6s or 7 are recommended for best performance.
The iPhone XS, X, 8, 7 and 6s offer the best balance of performance, weight, and field of view. Phones older than the iPhone 6 do not have enough processing power for mixed reality. iPhone "Plus" models with larger 5.5-inch screens are not supported by Bridge.