This is ballistic calculator. Features: 1005 reticles! Full reticle list see here: http://www.strelokpro.online/StrelokPlus - ability to scale scope reticle (reticle subtensions) to scope magnification (if reticle is placed to second focal plane). So, it's support different scope zooms and indicate current magnification. - Trajectory calibration ("Truing") feature. - current weather from internet weather-station - supports of PSI pressure units and internal barometer, humidity sensor and temperature sensor (if exist) - ability to select target type from long list of targets - ability to measure slope angle by phone camera - ability to input current altitude from internal GPS sensor