Great but drains battery

This is one of the beast tuning apps I have used. I am a section leader in band and I use it everyday to get in tune before I tune the band. It is very accurate, but lately I noticed it has been draining my battery with background activity. My phone was fully charged and then about 6 hours later it was dead and I didnt use it much during the day. Please fix this!!

spinningsong about TonalEnergy Tuner & Metronome