Can you verify if your iPhone battery drains faster during summer compared to other seasons with Zabbix? Of course you can!
I have always felt that during summer my phone battery drains faster than during the darker seasons. This would only be logical, as during summer the phone display must be brighter than during the darker seasons. Additionally, during summer we also tend to be more outdoors, so instead of home Wi-Fi the phone is using mobile data. On the other hand, during winter time if you are outdoors, the cold weather might affect battery life as well.