DUR-line Finder is a free Android app developed by Christian Dura. It falls under the category of Business & Productivity and is designed to work with the Satfinder SF 4000 BT, a satellite finder device that has a Bluetooth® interface. This app enhances the functionality of the Satfinder SF 4000 BT by enabling users to directly select the desired satellite on their Android smartphone, change the 8 preset satellites, select individual transponders of each satellite, and add new transponders to the respective satellites.

The app provides additional metrics such as level (in dB microvolts), C/N, BER, and MER, making it easier for users to adjust the Satfinder SF 4000 BT to their required settings. With DUR-line Finder, users can also change the LNB oscillator frequency and switch on or off the sound signal. The app requires Android 4.4 or later and supports Bluetooth Low Energy (BLE) or Bluetooth Smart from Android version 4.4 onwards.