Main purpose: Heart rate monitor to beep me when i reach a certain heart rate when i go for run
Secondary purpose: It would be nice if it has gps so that it can collect my running statistica without bringing my phone

Is it most smart watch can be used without connected to phone and synq data to phone when i need it? I plan to only connect to phone once a while to synq the data (mostly after a run). I dont need the data to be constantly update to phone.