Operating Mode Full Touch Screen, Battery Capacity: 230mAh Big Battery, Bluetooth Version BT 5.0, Standby time: About 30 days, APP Name Da Fit, G-sensor / Heart Rate Sensor, Type: TFT IPS, Using time: About 7-10 days, Resolution: 360*360 pixels / 385PPI, CPU RealTek8762dk, Compatible OS Android system 5.1 version or above; iOS system 10.0 version or above, RAM 64KB, Color Black / Pink, Charging Type: Magnetic charging, ROM 64M, Model MAGIC 4, Size: 1.32 inch, 5ATM, Brand KOSPET.
Go down and check coupons out. Remember to check price history if it is available. What is the best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I can’t find any active coupons for this product in Banggood.
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): BGd596fc, BG285089, 6GSGIT, BGff98fe, BG28aa4b, BGc70579, BGHU1844, BG9ed413, BG5023a5, BG6985f6, BGHU1981
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Price history (for all/most countries) for KOSPET Magic 4 Smart Watch is here. The lowest price was: $29.99.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).