Unless you have some sort of obsolete bank then paying your landlord by check is just as easy/fast as any app.
This is how I pay rent:
1) login to bank website
2) click bill pay
3) put in amount in the right place (this was previously set up)
4) Click make payments
The bank then mails your landlord a check. You can even schedule payments automatically.
If get a new landlord:
1) click add company or person to pay
2) click person
3) Enter person's name, address, and phone number.
4) Click add person.
And do you expect your landlord to pay a premium to take a credit card?
You can also pay every one of your bills at the same time (credit cards, loans, etc...)
Which is why check payments dominate larger transactions. Merchant fees are expensive compared to an ACH check fee (25 cents tops).