I have bought a kroak mini gps tracker but when arrived the unit did not work proprely. I have sent an email to BangGood and receive an immediate answer asking me to describe my problem with photos and videos. After sending these information, I received an email telling me that the unit will be replace for free. After 3 weeks, I have received the new unit but same problem ! This tracker does not have a decent user manual and SW application is poor, the biggest problems are : - Only 2G network compatible (will soon deseapear in all countries). - Poor GSM sensitivity, it make the network connection radom and take ages to connect. - Very poor GPS sensitivity and quality, the GPS never locked on satelites on my second unit... Do not buy this product a big waste of time and money ! Unhappy Customer Ph. C.