Your smart scale is fine. Its app is the problem.

By Abraham BurnettReviewed October 18, 2026

The hardware is not the problem; the bundled companion app is. Once a scale's readings are in Apple Health, they sit in a store on your iPhone instead of only in the vendor's app, and any app you authorize can present them. This guide assumes an iPhone, because Apple Health does not run on Android.

Trendline is an iPhone app that reads Apple Health. Everything below assumes an iPhone; the escape route it describes is Apple Health, which Android does not run.

Two different complaints, one root

Spend an evening in scale owners' forums and the frustration sorts cleanly by price tier.

Premium scale owners are frustrated by the graph itself. When Withings redesigned its app in 2022, owners started a community thread asking for the old weight graph back: readings folded into averages, less visible day-to-day resolution (r/withings, 2022). That is a historical complaint, and this page does not claim the app behaves that way today. Complaints like it are about product decisions users publicly dislike, not broken hardware.

Budget scale owners are frustrated by everything around the graph. Themes that show up in vendor documentation, each in some apps and not others: apps built around an account (iHealth's MyVitals app creates one to store and sync your data, perits support article), data confined to one "main user" (eufy's support page says only the main user's data syncs to Apple Health), and subscription tiers around hardware you already paid for. Premium brands are not exempt: Withings now says automatic sync to third-party apps is part of its paid Withings+ membership for accounts created from October 13, 2026, while older accounts keep free sync (Withings official reply). The per-app pages linked below cite each behavior to its vendor documentation or App Store listing.

Why the companion app can't be the fix

The hardware was never the problem. The lock-in was.

None of this requires assuming bad intent. A scale maker's app is a hardware companion: it exists to pair devices, run firmware updates, and present every product the company sells. Weight display is one tile among many, built once for a whole product line. The observable consequences:

• In our judgment, the graph is one feature of a hardware companion, not the product. Statistical care, such as smoothing that resists one odd morning and honesty about sparse data, is what a dedicated trend view adds.
• Your reading history lives wherever the app keeps it. When a scale app is discontinued, that window can close: per Technodabbler, QardioBase tracking, history and sync stopped working in 2025 while the scale still shows a weight on its display, and no formal shutdown announcement was visible (Technodabbler's account, a secondary source).
• Switching scale brands means starting a new history in a new app, because each companion app keeps its own record of your readings.

In our judgment — and this is an opinion, offered plainly — the scale you researched and paid for deserves better software than a bundled companion app is structured to provide.

The neutral store you already own

Health is built into iPhone, and it is a store that is not tied to any one scale maker: Apple's Health data guide describes it collecting data from your iPhone, Apple Watch, and third-party apps and devices. Many scale companion apps, including those on the pages below, document an Apple Health connection. Once a reading lands in Apple Health, three things become true:

• It lives in Health, not in the vendor's app. Apple says Health data stays on your iPhone even if you delete the Health app itself. Apple does not spell out what happens to a source's past readings when that source's app is deleted or discontinued, so check Data Sources & Access in Health for your own scale's records.
• A new scale adds to the same data types. Change brands next year and the new app's readings sit alongside the old ones in Health's weight data, each labeled with its source.
• Any app you authorize can present it. An app reads only the data types you allow it to read (Apple's HealthKit authorization guide), so you are no longer limited to the bundled window.

One honest boundary: Apple Health's body-measurement types are weight, body-fat percentage, lean body mass, BMI, height, and waist circumference (Apple's HealthKit type list). Weight is the common ground. Composition extras vary by vendor, and some numbers on your scale's display (visceral fat, body-water percentage) have no Apple Health body-measurement type at all — the per-scale pages below state exactly what transfers for each brand.

What a real trend view does differently

Getting readings out of the silo is half the fix. The other half is reading them with statistical respect: a single morning's weight is dominated by water, food in transit, and timing — accurate and still noisy. A trend view worth trusting smooths deliberately, resists one odd reading, and says so when evidence is thin instead of drawing a confident line through sparse data. The math Trendline uses for this is public, on the methodology page.

Find your scale

Each page below states, with sources: how that scale's readings reach Apple Health (exact steps), what transfers and what doesn't, known failure modes, and what to do when sync misbehaves.

• Renpho: two App Store listings with similar names; which one to use, and what syncs
• Etekcity — the VeSync path
• eufy: the one-main-user limit on Health sync
• Withings: documented sync, a manual-refresh catch, and a rule for new accounts
• Fitbit Aria — weight and body fat % through the Google Health app; the older workarounds
• Garmin Index — cloud-first sync and its delays
• Fitdays: the app behind Lepulse and some other brands' scales
• OKOK International: the OKOK app and how it syncs with Apple Health
• Yolanda, Feelfit & FITINDEX: three apps with shared QingNiu software lineage
• My scale's app is gone: Qardio and other orphaned hardware
• Wyze Scale: the authorization path; check what actually transfers
• Xiaomi — two generations, two different apps; don't mix them up
• Omron — select scales only; better known for blood pressure
• Amazfit — the thinnest vendor documentation; what's actually verifiable
• iHealth — sync via MyVitals, account required
• Weight Gurus: the Greater Goods app
• No app at all? — the three setups that work without one

If your scale can't sync at all

Some scales have no Apple Health path — and a scale that only shows a number on its display is still a working instrument. You can add a weight reading to Apple Health by hand, and it is stored in Health alongside synced readings. (When two sources report the same data type, Health uses the one at the top of its source-priority list, per Apple.)

Trendline also accepts manual entries directly — including composition values Apple Health has no type for, like visceral fat and body water. If you'd rather try the idea first, the free weight trend calculator reads pasted weights in your browser.

Try the idea

Paste a few weeks of weights into the weight trend calculator — from any scale, any app, or a notebook — and compare the raw series against a deliberately slower signal. That contrast is the whole argument of this page, made with your own data.

Questions people ask

Sources

• r/withings: "New app update awful" (2022 redesign thread)
• Technodabbler: what happened to Qardio
• Apple: manage Health data on iPhone
• Apple: HealthKit quantity type identifiers
• Withings Support: official reply on third-party sync and Withings+
• iHealth: creating a MyVitals account
• eufy support: syncing to Apple Health (main user only)
• Apple: view your health data on iPhone

Trendline is not affiliated with or endorsed by any scale maker named on this page. Vendor behaviors change; this page states what was verifiable on the review date above, and each linked scale page carries its own verification date.

Related reading