Retrofit vs full replacement

Retrofit models sit over your existing thumbturn and keep the original key working. Full replacements swap the whole cylinder or nightlatch.

Connectivity

Bluetooth is fine for the door itself; add a bridge or choose Wi-Fi if you want remote unlocking and access logs.

Standards to look for

Check for a British Standard cylinder underneath the smart mechanism, and TS007 3-star or Sold Secure Diamond ratings.