?Notices?1.For installation, you may need installation frame kit, special ISO harness, amplifier adapter or caubus decoder which according to your car's situation. 2. Doesn't support factory car GPS antenna, back up rear camera, Bluetooth, USB and microphone ect. 3. Please note that it only supports JOYING accessories; DAB+ digital radio adapter, DVR , OBDII scanner, reverse camera, TPMS and steering wheel controller are not included in the delivery contents, but can be ordered additionally. ?GPS Navigation?Precise GPS engines, more accurate positioning, including GPS antennas, can better receive satellite signals, thus ensuring faster real-time navigation. Offline maps: If you are in an area where downloading the data of google offline map is supported, you can save the map data of that area to the car stereo in good map and use it offline. Synchronize mobile phone map data to head unit via Carply/ Android auto. ?Built-in 4G Module?Insert the SIM card for Internet access, but it cannot support to make phone calls or send SMS. Support the below types: FDD-LTE: B2/B4/B5/B7/B12/B13/B14/B17/B25/B26/B38/B66/B71. TDD-LTE: B41. ?Optical Fiber and Coaxial Digital Output?If your external amplifier has Optical Fiber or Coaxial Digital Input, it gives you a chance to achieve ultimate sound quality directly. ?Fast boot?once put in car key,it will start up at once and enter into user interface in 2 seconds.(It need about 30-40 seconds in the first time boot up).