I presume that the answer is “No,” but I thought I’d ask anyway. And any iPhone users might want to comment on whether the presence of HA’s near an iPhone or any other specified device can be used to unlock an iPhone (I know there is Face ID and all that - but with Smart Lock you don’t have to bother showing the phone your face).
For Android, amongst other things, your GPS position or the presence of a specified BT device near your phone, e.g., your smartwatch, can be used to unlock your lock screen. The problem is that the HA/Android phone connection (at least for my ReSound Quattro’s) does not show up as a standard BT connection. If I wanted, I could use the Phone Clip+ as an unlocking device but then I’d have to have the PC+ on and around all the time. I don’t want to have my watch using BT all the time because that chews watch watch battery and I don’t need the watch on BT all the time. (as an aside, a ReSound Multi-Mic, a remote mic, like the basic phone connection, is not a standard BT device w.r.t. a smartphone, and cannot unlock an Android phone).
Since the phone app is capable of recognizing the state of the HA’s (and the Multi-Mic)hru a (secure?) non-BT connection as well the PC+ through a standard BT connection, I’d like to suggest that we Android users all ding our HA OEM’s and Google to ask them to extend Smart Lock to recognize whether our very own HA’s are nearby as a way to unlock our phones. Another good thing would be to have some sort of proximity effect for unlocking. I haven’t experimented but it seems if BT broadcasting distance is 10 meters (> 30 ft) that you wouldn’t want to have your phone unlocked just when you’re in a room and someone else in your family could then play around with your phone, etc. (Lot of ignorance here on my part since normally I only use the Smart Lock feature when my watch BT is on and I’m holding the phone in my hand).
Of course, the Marvels don’t use an intermediary device, so Smart Lock works like a charm.
I have serious HA envy! Perhaps MFA will fix that as maybe HA’s running under MFA will be recognized as BT devices?! 
Jim,
It would appear that the problem is with your HA. You are using a ReSound HA and the Bluetooth you are using is not Bluetooth Classic, which is a requirement for Android Smart Lock to recognize. Your ReSound HA is using Bluetooth MFi (Made For iPhone) which isn’t recognized by Android.
My HA is a Phonak Audeo Marvel M-R 90 and uses Bluetooth Classic. I just checked and my Phonak Marvel HA is readily recognized as a Smart Lock device by my Android Pixel 3 XL phone. I don’t use Smart Lock at all since my fingerprint reader is on the back of my phone right where my index finger goes when I pick up my phone. My phone is always instantly unlocked only to me whenever I pick it up to use it.
Jim … I have Signa Pure 7pxM HA’s and an Android S7 phone. I agree that you’re suggestion for recognizing HA’s would be nice. I have an Siemens EasyTek which is recognized as a Trusted Device and unlocks my HA’s. My primary use of the EasyTek is for hands free phone calls. It has a mic for talking and my HA’s do the listening. My Android Smart Lock also can also use Voice Match to unlock phone although I’ve not tried it. Good luck.
@TraderGary, yes, I’ve been using the fingerprint reader but perhaps because of my case, I don’t always have 100% success. I’m a bit jealous of Marvel users but I guess when it matters the most, I could just switch on BT and use my watch, which I basically wear 24x7.
I’ve submitted my grain of sand request to Google to add HA’s as a Smart Lock device by hook or by crook. I’ll try sending the same bit of dust to ReSound, too!
I get frequent notifications to set up Smart Lock with each hearing aid, but it fails every time…
Forgot to mention…
This is with Marvel hearing aids and a Samsung Galaxy Note8.
The Bluetooth connection is a bit weird. It shows each aid, AND both aids.
I think I might have renamed the “both” connection, I can’t remember what it was originally. The “both” connection is the one used for SmartLock.
