Unlike a stopwatch, Timekept knows exactly how long your speech should be and provides clear color cues as well as optional sound and vibration alerts. If speaking: your time is much easier to read at a glance. If judging: you'll never miss a clap/bell again.
Among other features it will keep your screen unlocked so you can always check how much time is left.
Approximately $1 USD in your local currency; primarily because having an app on the store entails an annual cost and secondarily because making and maintaining a good app takes a great deal of time.
If you are in a country — or are too young — to have an App Store account with credit, let me know via the Support link below and I can probably send you a promotional code.