RedBearLab BLE Nano Kit v2 - nRF52832 is a compact module that would suit all your BLE needs.
This is not an Arduino, although it sure looks like one ! This is a feature-loaded, turbocharged ESP32 Wifi/Bluetooth Low Energy SoC development board for IoT applications.
SparkFun ESP32 Thing is the updated version of the ESP8266 that supports the Bluetooth low energy(BLE) that enables your IOT projects.
Bluetooth SMD Module - RN-41 (v6.15) is a small and reliable replacement for serial cables.
ESP-32S Wifi Bluetooth Combo Module is combined wifi+bluetooth solution provider for all kinds of applications like Iot and wearables.
Grove-BLE gives serial BLE function for robotic and remote control.
SparkFun nRF52832 Breakout is best suited for wireless applications that require consume low power.
LinkIt Smart 7688 Duo is an open development board jointly designed by Seeed studio and Media tek.
SparkFun Simblee BLE Breakout - RFD77101 provides your embedded project with a mobile app functionality.
RedBear Lab BLE Nano with MK20 USB board is the new application+accessory in one unit.
Linkit One is a development board offered by Seeed studio for all Iot platforms such as Wearables and Iot applications.