Heart-rate sensor accuracy
Optical sensor quality and sampling rate.
Why it matters
Cheap sensors lag badly during interval workouts, making training data useless.
What to check
Continuous monitoring drains battery; check the rated life with it on.
Electronics
Smartwatch & Fitness Band
Watches advertise 150 sports modes and . What actually matters is heart-rate accuracy during movement, quality if you run, and whether it survives a week off the charger.
Quick answer
Continuous heart-rate accuracy beats 100+ sports modes.
Built-in only if you run or cycle without phone.
AMOLED with always-on cuts battery in half.
7+ day battery with normal use.
In the shop
Ask the salesperson this exact question
Read these off your phone at the counter. The answer tells you more than the price tag.
1.“What is the battery life with always-on display and continuous heart rate on?”
A good answer: The real-use number. Brochure figures assume both are off.
2.“Are the health readings medically validated or wellness-only?”
A good answer: Honest answer is wellness-only for most watches. Anyone claiming medical accuracy is overselling.
Find your fit
A few questions about your situation, not about the product.
0/20
Add one short need not covered above.
Answer all 3 questions to see the spec sheet to shop with.
Extended warranty & AMC — what to check before you say yes
For electronics the expensive failures are the display, the board and the battery. Extended cover is worth it only when it names those parts and offers a repair path in your city.
Ask these five questions
- ✓Is the display / motherboard covered, and up to what value?
- ✓Is accidental and liquid damage included, or is that a separate add-on?
- ✓Is repair done at an authorised service centre with genuine parts?
- ✓Is battery degradation covered, and below what health threshold?
- ✓What's the turnaround promise, and is a standby device provided?
Usually not covered
- ×Theft and loss (that's a separate insurance product)
- ×Software issues, data loss and unauthorised repairs
- ×Batteries and chargers on most plans
- ×Cracked screens unless accidental damage is bought explicitly
Rule of thumb: worth considering on a high-value device you carry around, rarely worth it on a low-cost one where a plan costs more than ~15% of the price.
These are comparison links, not recommendations — we don't sell plans and we don't rank providers. Some outbound links on KnowBeforeBuy are affiliate links. Cover, exclusions and pricing change; read the plan document before you pay.
Check resale value of your old device
If you are upgrading, a buyback quote changes the real cost of the new purchase.
Get a quote onCashify
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Buy it locally
Shops near you that stock smartwatch & fitness band
Sometimes the local dealer beats online on price, installation or the exchange offer. Tell us where you are and we'll list nearby stores. We don't rank or take money from any shop; results come from Google Maps.
The area you enter, or coordinates rounded to about 1 km if you use your location, are sent to Google Maps through Lovable to find places. Lookups are temporarily cached for up to 30 minutes.
The spec sheet, decoded
Built-in GPS vs connected GPS
Own chip vs borrowing the phone's.
Why it matters
Runners and cyclists need built-in to leave the phone at home.
What to check
'' in the spec list often means connected GPS only.
Display type & brightness (nits)
AMOLED vs LCD and outdoor visibility.
Why it matters
Under Indian sun, below 500 is unreadable.
What to check
Always-on display cuts battery life roughly in half.
Battery life in real use
Days with your features on.
Why it matters
Quoted '14 days' assumes AOD off, HR sampling low, unused.
What to check
Ask for battery life with always-on display and continuous HR.
Water resistance (ATM / IP)
5 means swim-safe; IP68 means splash and rain only.
Why it matters
Swimmers must have 5 ; IP68 watches fail in a pool.
What to check
IP68 is not the same as 5 .
SpO2, ECG and BP claims
Health sensors on the wrist.
Why it matters
Only medically certified is meaningful; wrist readings are indicative at best.
What to check
Treat these as trend indicators, never as diagnosis.
Ecosystem & app support
How well it works with your phone.
Why it matters
iPhone users lose call/reply features on many Android-first watches.
What to check
Check notification reply and call support for your phone.
Before you pay
- ✓Decide if you need built-in (outdoor running/cycling) or not.
- ✓Ask for battery life with always-on display and continuous HR enabled.
- ✓Confirm 5 if you swim; IP68 is not enough.
- ✓Check strap size and replaceability for your wrist.
Common traps
- !Buying for '150 sports modes' — most are just timers.
- !Trusting wrist or as medical readings.
- !Android-first watches paired with iPhones, losing half the features.
Budget bands to running watches and premium smartwatches.