My application is similar to a reminder service that reminds users of events that they scheduled. I'm sending emails to users through a PHP script. I'm not sending one email to multiple recipients. Each recipient receives a different message. I plan to use cron jobs every minute and expect the application to send roughly 200 individual emails in 1 hour (for a small user base that may grow).
I don't have hosting experience with this type of application. I plan to start on a shared host and move up in the future to vps or dedicated. Most shared hosts that I looked into allow 50-100 emails per hour with delays between mailings. Please kindly inform me what I should look for in web hosts for this kind of application.