What is the maximum number of bonded i.e. 'Paired Devices' for Bluetooth LE devices in Android?

Question

The information being sought with this question is I think similar (but not the same) as the information sought here...

"How many devices we can pair via Bluetooth of BLE to Android?"

...and so let's re-ask it a different way:

Let's say we have a use case where someone with a mobile phone may want to connect securely (using industry standard security mechanisms) to a Bluetooth LE device using Pairing. When Pairing occurs, bonding information is stored in the mobile phones - - > Settings - - > Wireless - -> Bluetooth - - > Paired Devices window (dialog).

These 'Paired Devices' will remain present in this list regardless of whether or not active connections are maintained, correct?

And if this answer is correct, how many hundreds or thousands of previously Paired/bonded devices can be accrued in this list before the Android OS (or iPhone's iOS) begins to start to incur performance issues?

My understanding is... neither Android OS or iPhone OS offer programmatic ability to 'clean out' the list of old paired / bonded devices. And mobile phone users who neglect to remove those devices manually could have a challenging task at hand if they've allowed the list of Paired/Bonded devices to get out-of-hand.

Thoughts? Thanks much in advance, --DJ Regan

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2018-November-12 Update... New news today: In profiling many BLE paired devices with Android - - > a team mate of mine discovered their Bluetooth radio had become unavailable (as in un-useable) after attempting to pair to the 102nd device+ today. Additional profiling is on-going. So... perhaps this is a use case that neither iOS or Android should be trusted to support? --DJ Regan

Answer 1

From sources I guess 100 is the right number pointing to the max devices you can bond with. Also proved in practise.

 /* The number of security records for peer devices. */
    #ifndef BTM_SEC_MAX_DEVICE_RECORDS
    #define BTM_SEC_MAX_DEVICE_RECORDS  100
    #endif

...

/************************************************************************************
    **  Local type definitions
    ************************************************************************************/
    typedef struct
    {
        uint32_t num_devices;
        bt_bdaddr_t devices[BTM_SEC_MAX_DEVICE_RECORDS];
    } btif_bonded_devices_t;