This is a Bluetooth Smart Watch by Vkaka. With a sleek, modern design, brilliant 1.54" OLED display. Stainless steel surface, precision laminating process. Nano TPU85 material strap, anti-sweat matte surface treatment, ergonomic convex design and soft strap, which make wearing more comfortable. Life water resistant, the smart watch surface can resist rainwater impact when you are in outdoor. Bluetooth model: Just connect the smart watch with your phone via Bluetooth, then download and install the APP (BTNotification or FunRun or Fundo), so you can read Whatsapp,Twitter,Facebook and other application push messages, make or receive calls, view and reply text messages etc.. ?SIM card model: If you install a GSM 2G/2.5G Network SIM Card into the smart watch, you can make phone call directly from the smart watch, including answering and dial-up, send/reply messages. Activity Tracker: Pedometer, sleep monitoring, sedentary remind. Other functions: Image viewer, Sound recorder (need put and SD card ), Remote capture, Alarm clock, Calendar,Camera (0.3M),Two way Anti-lost. his smart watch can support most android and ios phones. Such as iPhone X/XS/XR/8/8 plus/7/7 plus/6/6 plus/6s/6s plus/5/5s (Only Supports Partial Functions), Samsung Galaxy S9, S9 Plus, S8, S8 Plus, S7, S7 Edge, S6, S6 Edge, S5, Samsung Note 8, 5, 4, Google Pixel/Pixel XL, HTC, Sony, LG, HUAWEI, ZTE etc. smart phones.