If the “1% battery” icon is our modern-day nightmare, the “cable octopus” at the bottom of our bags is a close second.
Let’s be honest. You have that cable. The one you swear you packed, but can’t find. You have the other cable, the one that’s frayed at the end and only works if you hold it just right. And you have the wrong cable: the Micro-USB one that time forgot, which is useless for your new USB-C-everything life.
A power bank doesn’t just mean carrying a brick; it means carrying a leash. And in 2025, that entire setup feels archaic.
Anker, a brand that has built its empire on solving our charging anxieties, thinks it has the ultimate solution. It’s not just another power bank. It’s the Anker Nano Retractable Power Bank (A1638).
On paper, this S$79.99 device is the perfect “all-in-one” pocket rocket. It’s a 10,000mAh battery (good for 2+ phone charges) with a blazing fast 45W output. It has a smart screen. And its star feature: a built-in, 70cm retractable USB-C cable.
No more forgotten cables. No more tangled messes. This is the grab-and-go dream. But as we’ve learned, when you pack this much power and tech into a tiny chassis, there are always trade-offs. We’ve been testing it, and the question is: Is this the perfect gadget, or is it a dangerously hot compromise?
The “Why Didn’t Anyone Do This Sooner?” Feature
Let’s start with the one thing you’re buying this for: the cable.
Anker calls it the “InstaCord,” and it is, quite frankly, a game-changer. You pull the USB-C plug, and a 70cm (2.3 ft) cable spools out. That’s not some tiny, useless 10cm nub; it’s a genuinely useful, long cable. It’s long enough to have the power bank in your bag and your phone in your hand, or to have the pack on the floor while you’re plugged in at a café table.
When you’re done, a firm tug retracts it cleanly back into the body. Anker, anticipating our skepticism, says it’s durability-tested for 20,000 pulls and 20,000 bends. It feels robust. This single feature eliminates the primary friction point of portable charging.
The device itself is impressively compact for a 10,000mAh unit. It’s a bit chubbier than the A1665 wireless pack we’ve looked at before, but still small enough for a jacket pocket or a small sling bag. It comes in a range of colours (Black, White, Blue, Pink) to match your aesthetic and includes a lanyard.
And then there’s the screen. It’s a bright, full-colour TFT display that shows you the remaining percentage, the power (in watts) being drawn, and the estimated time to recharge the pack. It looks high-tech and incredibly useful.
The 45W Power Promise (On Paper)
The A1638 isn’t just convenient; it’s fast. That built-in cable and the separate USB-C port both support a 45W Max output.
To put that in perspective, that’s not just “fast charging”; that’s “Super Fast Charging.” Anker’s specs say it can juice up a Samsung S24+ to 50% in just 25 minutes. This is thanks to its support for PPS 2.0 (Programmable Power Supply), the standard Samsung uses.
This makes the A1638 one of the most compelling options on the market for Samsung users, who are often left in the lurch by “Made for iPhone” accessories. That 45W is also enough to charge a MacBook Air, a Steam Deck, or an iPad Pro at respectable speeds.
With a 10,000mAh capacity, it holds enough power for about two full charges for most flagship phones (like an iPhone 15 Pro or Samsung S24).
A built-in 70cm cable, a 10,000mAh capacity, and a 45W output. For S$79.99, this seems to be the one power bank to rule them all.
…Right?
The Real-World Bottlenecks
This is where our real-world testing runs head-first into the marketing. This device’s incredible convenience comes with a few very significant, and very hot, asterisks.
1. The 45W ‘Sprint’ (and the Heat)
When you plug this in, it is genuinely fast. You’ll see your phone’s “Super Fast Charging” notification pop up, and the watts on the little screen will climb. But it can’t hold that speed.
After about 10 minutes of outputting at 45W, this little power bank gets hot. We’re not talking “comfortably warm”, we’re talking “toasty.”
And just like the A1665, the A1638 has safety systems that kick in. To protect itself (and your phone), it throttles the power output. That 45W burst is a “sprint,” not a “marathon.” It’s fantastic for a quick 20-30% boost, but don’t expect it to sustain that speed for a full 0-100% charge. For a device aimed at the “Aesthetic Explorer,” a gadget that gets this hot can be a little alarming.
2. The “3-Device Charger” Myth
The A1638 has three outputs: the built-in cable, a USB-C port, and a USB-A port. The spec sheet says it can “charge up to 3 devices.”
Technically, this is true. In reality, you should almost never do this.
When you plug in a second or third device, the 45W output collapses. The total shared output drops to a measly 22.5W, meaning each device can get as little as 7.5W. That’s “slow charging” from a decade ago. It’s barely enough to keep your phone’s battery from dying, let alone charge it.
Think of this as a “one device, fast” charger. The other ports are for low-power emergencies only, like juicing up your wireless earbuds.
3. The “Hurry Up and Wait” Recharge
This is, by far, the A1638’s most significant and most annoying flaw.
It can output at 45W. But it can only recharge itself at a maximum of 30W. And just like its output, it can’t even hold that speed.
Our research and testing show that after about 10-15 minutes of recharging at 30W, it throttles down to 20W for the rest of the cycle. The result? A full 0-100% recharge of the power bank itself takes nearly two hours.
This creates a frustrating user experience. You have a “fast” power bank that is itself slow to get ready. This is a major bottleneck. If you’re the type of person who forgets to charge your gear overnight and needs a quick top-up of your power bank before you run out the door, this device will let you down.
The Final Verdict: Who Is This Actually For?
The Anker Nano Retractable Power Bank (A1638) is a product of brilliant convenience and frustrating contradictions.
At S$79.99, it’s priced competitively. But your satisfaction will depend entirely on your user profile.
This power bank is PERFECT for you if:
- You are a daily commuter or student.
- You are organised. You remember to plug in your power bank overnight (making the 2-hour slow recharge a non-issue).
- Your main problem is forgetting your cable.
- You need fast, 20-30% top-ups during the day (like on the MRT or during a lunch break), where the 45W “sprint” is ideal.
This power bank is NOT for you if:
- You are impatient and often need to “fast charge” your power bank before leaving.
- You are a power user who needs to charge multiple devices at once.
- You need sustained 45W+ output for long sessions on a laptop or Steam Deck.
The A1638 successfully solves the “cable” problem, but it introduces a “recharge speed” and “heat” problem in its place. For us, the sheer convenience of the built-in cable just about wins out, but only if you know exactly what you’re getting into.
The DANAMIC Take
The Anker Nano Retractable Power Bank (A1638) is a product of brilliant convenience and frustrating contradictions. It’s a near-perfect “all-in-one” solution for the daily commuter.
It completely solves the “I forgot my cable” problem with its fantastic retractable “InstaCord,” and its 45W sprint speed is a lifesaver for quick top-ups.
However, it stumbles on two major points: it runs uncomfortably hot under load, and its painfully slow 2-hour self-recharge feels completely out of sync with its “fast” persona. It’s a device that’s 90% of the way to being the perfect gadget, but that last 10%—the heat and the slow recharge—are compromises you will feel.
The Anker Nano Retractable Power Bank (A1638) is available in Singapore now at the official website, Shopee, and Lazada.
For more information, visit https://anker.com.sg/ or follow Anker Singapore on:
- Instagram: @Anker_Singapore
- Facebook: AnkerSingaporeStore
- YouTube: @ankersingapore6549
- TikTok: Anker Singapore
Anker Nano Retractable Power Bank (A1638)
Pros
- The 70cm retractable cable is genuinely useful and robust. It’s the perfect "all-in-one" solution for commuters and minimalists.
- A great "sweet spot" of 10,000mAh capacity in power-to-size, good for ~2 full phone charges.
- The 45W output with PPS support is fantastic for Samsung users and great for a quick, 10-minute "sprint" charge for any USB-C device.
- The real-time data on wattage and time-to-recharge on the bright, full-colour TFT display is a genuinely useful feature.
Cons
- This device runs very hot when at 45W, which causes it to throttle its speed significantly after just 10-15 minutes.
- The 2-hour recharge time is a major bottleneck and feels archaic for a "fast" power bank.
- Don't buy this to charge 3 devices; it's a single-device fast charger, and a multi-device trickle charger.
