T-Mobile must be happy with Nexus 4 sales thus far, as the carrier has just announced it will be expanding distribution of Google's handset to its entire retail chain. Despite ongoing supply constraints, the rollout began yesterday and T-Mobile says all stores should have stock "in the coming weeks." Furthermore, you'll be able to buy the device from its website beginning January 23rd. Prices remain the same at $199 on-contract and $499 fully unsubsidized. The Google / T-Mobile relationship is also growing with a new variant of the HSPA+ 32GB Nexus 7 that includes a T-Mobile SIM card. It's available immediately from Google Play for the same $299 price point as the existing AT&T model.