Discharging

[John_p]

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Model Name:
Firmware Version:
Rooted or not:
Frequency of Occurrence:
APP Name & APP Version (If your issue relates to the app):
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19% for 40 minutes of WhatsApp seems to be too much . Even system UI takes 19% which is too much kindly fix this bug

[ARP_ASUS]

Hi John p,
For Battery App usage battery time can be sometimes inaccurate, the main stats which matters is Screen on time. If that gives you a good no. then I think there is nothing to be worried about. 
You can do a battery stats reset and try a couple of cycle - Charge to around 95% and drain till 10% this way the stats should Auto reset and may give accurate readings. 
Make sure your phone is on the latest firmware version is .70

[KKP]

@John p

Suggest you to use accubattery app from playstore. I observed inaccurate battery usage statistics after .70 update in system battery settings.
You can see that battery settings is showing Hotstar app used for 1 hr 30 mins and consumed 48% of the battery and COD Mobile game used for 4hr 46 mins and consumed 20% of the battery.