Why not just use email
Because you end up comparing nine applicants across forty messages, and the one detail you need is in the thread you did not keep. Applications hold the same fields for every applicant, so comparing them is reading a list rather than an archaeology exercise.
Viewings
Book a viewing from the application, at any point before you decide. The applicant confirms or offers other times by email, gets a calendar file, and you both get a reminder on the day. Afterwards, mark whether they came.
Viewing times and notices, in an agency workspace
Add the times you can do to an advert under Viewing times, one time or a block, such as every 15 minutes from 10:00 to 12:00, with how many applicants each takes and who attends. The advert and the apply page show the times still free, and a pick books the viewing at once, with the confirmation, the calendar file, the reminder on the day and the attended or no-show record. Two applicants can never both take the last place. The letting pipeline also has a Notice given column: a let whose tenant has given notice, with a link that opens the advert form available from the day after they leave.
The waiting list
Most enquiries arrive for a property that is already gone. A waiting list turns that from a dead end into your first call next time something comes up, which is the cheapest tenant find there is.
Then referencing
When you have chosen someone, order a reference from their application, with their details already filled in, rather than making a judgement on the strength of a good first impression. When you make them the tenant, their name, email, phone and move-in date carry across, and a tenant already living there stays current until the new tenancy starts.