<i>FIND3</i> is a minimal Android app for using with <a href="https://www.internalpositioning.com/">FIND3</a>. This app will allow you to use your phone to perform constant scans of Bluetooth and WiFi signals and levels that can be associated with certain locations in your home to allow internal positioning. To receive the data, the <a href="https://github.com/schollz/find3">FIND3 public server</a> can be used or a personal server can be deployed. The Framework for Internal Navigation and Discovery (FIND) is like GPS, but for your every room in your house/business, with using only a simple smartphone or laptop. Your device (laptop or a smartphone) tracks itself by actively scanning for nearby Bluetooth/WiFi devices and records their signal strengths and classifying them based on known signal strengths for a given location. This repository is a complete re-write of the [github.com/schollz/find previous version of FIND]. The API for sending fingerprints (/track and /learn) is backward compatible. There are several notable improvements on the previous version: * Support for any data source, Bluetooth / WiFi / magnetic fields / etc. (previously just WiFi) * Passive scanning built-in (previously required a separate server) * Support for Bluetooth scanning in scanning utility (previously just WiFi) * Meta-learning with 10 different machine learning classifiers (previously just three) * Client uses Websockets+React which reduces bandwidth (and coding complexity) * Rolling compression of mac addresses for much smaller on-disk databases (see mapslimmer) * Data storage in SQLITE-database (previously it was BoltDB)