This is the English edition of a review from my Japanese YouTube channel, iestaLife. I review gadgets from my home studio in Japan, so product links go to Amazon Japan.
Quick take
I compared three thin cases for the iPhone 16 Pro Max: the memumi 0.3 mm matte case (2,399 yen), the Sinjimoru M-AiroFit Basic clear case (999 yen) and a 100-yen case from Daiso. The memumi is by far the lightest at 12.9 g and became my daily case. The Sinjimoru has the strongest MagSafe magnet. The Daiso case surprised me with the best-feeling buttons, but it has no MagSafe.
What I tested
- Three cases on a white iPhone 16 Pro Max: memumi matte (MagSafe magnets), Sinjimoru clear (MagSafe magnets) and a plain Daiso case
- Weight on a scale, fit, button feel (including Camera Control and the Action button), the USB-C cutout with different cables, screen and lens lips, and MagSafe strength with a ring, a stand and a car mount
- Why I bought them: my previous 2,480-yen thin case cracked at the edge after many on-and-off cycles
What I found
| Case | Price (at recording) | Weight (measured) | MagSafe | Buttons | USB-C cutout |
|---|---|---|---|---|---|
| memumi matte (0.3 mm) | 2,399 yen | 12.9 g | Yes | Easy to press | No issues |
| Sinjimoru clear (M-AiroFit Basic) | 999 yen | 24.7 g | Yes, strongest of the three | A bit stiff | Wide, no issues |
| Daiso 100-yen case | 100 yen | 26 g | No | Best of the three | Narrow; bulky cable plugs do not fit |
- memumi: fits snugly, silky matte finish, feels closest to a bare phone. The raised lip between the lenses felt unnecessary to me, and with a glass screen protector the screen-side lip is borderline. Hard to take on and off.
- Sinjimoru: easier to install, and the magnet was strong enough that my ring stayed on the phone instead of the car mount. The edges do not wrap around, so it looks a bit like the phone sits in a plastic tray, and the Action button is stiff.
- Daiso: accurate fit and clicky, light buttons. The cutout is small: the Apple cable fits, but cables with a thick plug do not. A MagSafe ring cannot hold the weight of the phone on it.
Who it's for
Pick the memumi if you want the thinnest, lightest feel. Pick the Sinjimoru if you rely on MagSafe rings or car mounts and want one case that just works. The Daiso case is a fine stopgap if you do not use MagSafe accessories, but it is only sold in Daiso stores. Whichever you choose, treat ultra-thin cases as consumables; they can crack if you remove them often.
Watch the full review
The video is in Japanese. YouTube auto-translated captions may help. Useful timestamps: about 3:15 weights, 4:30 the memumi fit, 8:00 the Daiso case, 9:00 the USB-C cutout test, 12:45 MagSafe strength.
Limitations
These are first impressions on the day I installed each case, not a durability test. All three are iPhone 16 Pro Max cases, so check the listing for your model. Prices are Amazon Japan and Daiso prices at the time of recording.
Products
memumi 0.3 mm ultra-thin MagSafe case for iPhone 16 Pro Max (matte): on Amazon Japan
Sinjimoru MagSafe clear case for iPhone 16 Pro Max (M-AiroFit Basic): on Amazon Japan
The Daiso case was bought in store and has no online link.
The Amazon Japan links above are affiliate links. As an Amazon Associate, I earn from qualifying purchases. Check the listing for the exact model, color, current price and shipping availability in your region.
More reviews in English
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This review is also available in Japanese.