Traditional PGO can improve CPU-bound applications, but it doesn't work well for some mobile applications which are more concerned with startup time and binary size. We recently extended LLVM's IRPGO framework to support Temporal Profiling to measure an app's startup behavior. We've also created a new algorithm to generate orderfiles called Balanced Partitioning which uses temporal profiles to reduce .text section page faults during startup and can even reduce compressed binary size. And finally, we have a tool to measure an iOS app's page faults on a device to showcase our results. This talk will be useful to anyone interested in understanding how IRPGO can order functions to improve start performance and compressed size.