When you plan to use ANNA-112 module, do you find that the size is really very small, but difficult to assemble.
Why not choose feasycom FSC-BT630, Noridc 52832 module.
The FSC-BT630 is a small size module, but very easy to assemble.
And it includes 32Khz (Low Frequency Crystal).
I10*11.9*1.8mm size, with CE, FCC, IC, KC certification. It is suitable for many kinds of application such as medical device, low energy device, wearble device, beacon device ext.