A smart lock that can be retrofitted to almost any door has been launched by a California company using a Bluetooth chip from Nordic Semiconductor. An important factor is that Level Home's lock is compatible with both Apple HomeKit and Amazon Sidewalk for voice control from smartphones and Alexa smart speakers. The Level Lock uses the Nordic nRF52840 Bluetooth 5.2/Bluetooth LE multiprotocol System-on-Chip (SoC) and enables instant and secure keyless access for authorized users. It is powered by a single Li/MnO2 battery, which provides up to a year of battery life under normal use thanks to the low current characteristics of the nRF52840. The fully automatic power management system reduces power consumption by up to 80 percent compared to the Nordic nRF51 series. The chip combines a 64MHz, 32bit ARM Cortex M4 processor with floating point unit (FPU), with a 2.4GHz multi-protocol radio (supports Bluetooth 5.2, Long Range, Bluetooth mesh, ANT, Thread, Zigbee, IEEE 802.15.4, NFC and proprietary 2.4GHz RF protocol software), with 8dBm output power -95dBm RX sensitivity for a link budget of 103 dBm, with 1MB Flash memory and 256kB RAM. The Dynamic Multiprotocol feature supports simultaneous wireless connectivity of the protocols. The Level Lock uses the 7 x 7mm chip in the combination of stainless steel and reinforced metal alloys to meet US industry standards for safety, durability and reliability certified by the Builder's Hardware Manufacturers Association (BHMA). During use, the smart lock pairs with a user's Bluetooth 4.0 (or newer) smartphone using Bluetooth LE. From the 'Level Home' app, users can then automatically lock and unlock their doors without the need for a physical key, and send digital keys to authorized guests, such as a merchant, friend or babysitter. From the app, users can also set specific access periods for guests with a 'Party Pass' feature, create a single event pass for multiple people