The answer depends on the Fold8 model. The Ultra lasted longer than iPhone Duo in a published test table, while the standard Fold8 lasted less time in a simultaneous comparison. Samsung also offers charging protection, with battery tracking available through the multi-device battery monitoring app “Maqbis” on Android.
When you pay for a foldable phone, you want a large screen you can actually use, without having to close it for fear of running out of battery. That makes the comparison between iPhone Duo and Samsung Fold8 worth more than a glance at capacity figures.
To find out which phone gives you more time between charges, we will compare iPhone Duo with the standard Fold8 and Fold8 Ultra in terms of battery capacity and runtime test results.
What do we know about the iPhone Duo battery?
Apple lists two built-in rechargeable lithium-ion batteries, and the energy information on its French website gives a rated capacity of 4883 milliamp-hours (mAh). This is the combined capacity of both batteries, not the capacity of each one. Source: Apple specifications and Apple energy information.
The screen you use also affects the advertised runtime. Apple says video playback can reach 44 hours on the outer screen or 31 hours on the inner screen. These are results from the company’s tests, rather than a promise of the same runtime while taking photos, making calls and switching between apps. Source: Apple specifications.
Is the Samsung Fold8 battery really bigger than the iPhone Duo battery?
Before comparing them, note the difference between Typical capacity and Rated capacity. To determine typical capacity, a sample of batteries of the type used in the phone model is tested, and their average capacity is estimated; capacity can vary slightly between batteries of the same type. Rated capacity is a value the manufacturer declares according to a measurement standard. We will therefore give each type of figure its own column.
| Phone | Advertised typical capacity | Rated capacity |
|---|---|---|
| iPhone Duo | No unverified typical capacity used here | 4883 mAh |
| Samsung Galaxy Z Fold8 | 4800 mAh | 4660 mAh |
| Samsung Galaxy Z Fold8 Ultra | 5000 mAh | 4854 mAh |
Sources: Apple information and Samsung specifications and footnotes.
That is why the Ultra’s advertised figure alone cannot establish that it will last longer. Runtime needs to be tested and depends on the screen, brightness, network and how you use the phone.
What do runtime tests show?
Tom’s Guide published the following results:
| Phone | Runtime in the site’s table |
|---|---|
| iPhone Duo | 13 hours and 20 minutes |
| Standard Fold8 | 10 hours and 6 minutes in the revised test |
| Fold8 Ultra | 14 hours and 33 minutes |
The source says iPhone Duo and the standard Fold8 were tested simultaneously after the test was revised, but does not confirm this for the Ultra. It also mentions a different earlier result for the standard model. The Ultra records a longer runtime in this table, but the figures do not establish that every Fold8 model leads in every kind of use. Source: original test.
Where might Samsung suit you better?
If your priority is managing charging and tracking the battery from another Android phone, there is a practical benefit worth considering. Samsung’s settings offer Battery protection to reduce the time the battery stays full, with available options varying by device and system version. Source: Samsung support.
The multi-device battery monitoring app “Maqbis” complements this habit with indicators that help you understand your battery: estimated capacity and battery health over time, drain during active use and idle periods, and charging power, duration and temperature. Together, these let you spot changes in performance, review your habits and compare charging sessions instead of relying solely on the current charge level.
If you use another Android phone, you can share your Fold’s battery readings and view its details there. For example, leave the Fold charging and follow its estimated time to full and charging temperature from your second phone, with a full-charge alert to help you keep track. Samsung’s settings control the charge limit, while the app helps you understand and monitor what is happening.
How do you choose based on the battery?
Identify the model first, then look for a test that matches your use: browsing on the inner screen, watching video or working with multiple apps. Compare charging speed separately from runtime, as they are different benefits.
If you want to track batteries across a group of Android phones, the features of the multi-device battery monitoring app “Maqbis” become part of the practical comparison. If your priority is simply how long a charge lasts, do not rely on the manufacturer’s name or capacity figure; start with results for the specific model, and understand the test conditions.
Frequently asked questions
Is the Fold8 battery bigger than the iPhone Duo battery?
The standard Fold8 has an advertised typical capacity of 4800 mAh, and the Ultra has 5000, while Apple lists a rated capacity of 4883. These figures do not all use the same type of measurement: the Ultra’s rated capacity is 4854, and the standard model’s is 4660.
Which phone lasted longer in the cited test?
iPhone Duo recorded 13 hours and 20 minutes, and the standard Fold8 recorded 10 hours and 6 minutes in a simultaneous test. The table lists 14 hours and 33 minutes for the Ultra, without confirming that it was tested alongside them.
Can I use the multi-device battery monitoring app “Maqbis” on iPhone Duo?
The multi-device battery monitoring app “Maqbis” is currently available for Android phones.
