I see no reason to check in the day prior with the app. For example this week I sit in a lobby two+ hours after my “arrival time” check in that I did yesterday, waiting for a room.
I do it, but can't say it really helps with any certainty.
I do it to help them prepare for their stays and avoid the crunch time of check in. Perhaps it buys me some goodwill and flexibility, but at the very least it saves me a tiny bit of time of them verifying my credentials.
It would help more if it were like Hilton and mobile checkin meant you could bypass the counter altogether and go directly to your room and unlock the door with the app. The way it's setup at Marriott doesn't save a lot of time since you have to stop by the counter to pick up your key anyway. Have you ever been stuck behind a group of stranded passengers at midnight, when there's only one counter agent trying to checkin an entire cancelled flight, just to pick up your room key? You're better off giving up and going to another hotel entirely.
I can't choose which way to vote, because it's been very inconsistent for me. Most of the time, it makes no difference in regards to the amount of time it takes to check in. The desk staff still makes you go through the whole process and won't process mobile check-ins ahead of other guests, even though there's a separate line for mobile check-ins.
On the few occasions where it has actually worked and I was able to walk in, show ID, and get a ready-made key handed to me, I've very much appreciated it. It would be great if things were consistent across the board, but it seems most hotels don't even seem to know what mobile check-in means.
At a couple of properties, my app has mentioned mobile key-cards, but I still haven't actually encountered a hotel with this feature activated yet.
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