Until you get no payment you really can't do much but wait.You could offer a early mutual lease termination with 2 month rent penalty all off the lease..All sign. and security deposit is returned after move out to parties as set out in termination agreement to be agreed on in advance in this case. but check your state landlord laws to make sure what you can charge for on that, each state has guidelines. 

Compare that to just giving the tenant their security deposit to get lost in x number of days.

Look for bank deposits, checks paid, etc.Tax records are a good source as well.

Irish banks require 10% deposit on mortgage up to 220K and 20% down payment on anything higher than220K.

You have to pre-register for all counties and there is a deposit required of 5K for most counties. 

Blake King FDIC just means federal deposit insurance basically every bank in the us should have it.

If you get the leases everything you need to verify will be on there; security deposits, rent amount, who is responsible for what, etc. 

You don't need to tell them anything, other than their tenancy is going to end on x date, and we can set up an appointment for a walk through before discussing your security deposit

You can also ask for a non-refundable option to buy deposit.  

Similarly if your bank has an app that does mobile deposits that's probably worth looking into.There probably are apps like you're talking about and I'm just unaware of them, so it would be nice to see what others have to say.I will say that there are some big property management solutions such as Buildium and Appfolio, that probably have apps which tie into their system and provide some of the tenant and building/portfolio tracking that you're asking about - but those systems as a whole aren't necessarily cheap, either.Personally, I just make sure to carry around at least one envelope - so I can always do "back of the envelope" calculations when necessary :D