Last updated: August 2026
The S7 edge was praised above all for battery life — it paired a large cell with a display and processor that were not especially demanding. That combination is worth understanding, because battery capacity alone is a poor guide.
Capacity is only half the equation
Battery life is capacity divided by consumption. A phone with a smaller battery can easily outlast one with a bigger battery if it draws less power.
What drives consumption:
| Factor | Effect |
|---|---|
| Screen size and brightness | Usually the largest single draw |
| Refresh rate | 120Hz costs noticeably more than 60Hz |
| Processor efficiency | Newer chips often do more for less |
| Screen resolution | Higher resolution costs power |
This is why comparing two phones on capacity alone tells you very little. Look for real-world endurance results instead.
What you can control
- Cap the refresh rate if your phone allows it — often the easiest saving
- Lower the screen brightness, or use automatic brightness
- Replace an ageing battery rather than the phone
That last point matters most. Batteries degrade with cycles and age — a phone that no longer lasts a day often needs a battery, not a replacement.
Where the S7 edge stands now
From 2016, long past software support, with a curved display carrying the usual accidental-touch and repair-cost drawbacks. Do not buy or finance one.
See why curved screens fell out of favour.
See Galaxy S7, Galaxy S8, Galaxy S range and Samsung contract deals.
Frequently asked questions
Does a bigger battery mean longer life?
Not necessarily. Consumption matters as much as capacity.
What uses the most power?
The screen, usually — size, brightness and refresh rate.
My phone no longer lasts a day. What now?
Try a battery replacement before replacing the phone.
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This is general information, not financial advice.