Comparison

nag vs ContactOne

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

nag

This app ensures you never forget tasks by repeatedly sending notifications until they are marked as complete. It offers flexible scheduling for recurring and one-time reminders, with options to snooze or dismiss directly from the notification. Additional features include a focus timer, logbook, and home screen widget.

Highlights
  • Reminders that don't give up
  • Postpone from notification
  • Reliable repeat scheduling
  • Set reminders in seconds
  • Focus timer and logbook
  • Works fully offline
  • No account needed
Features
Read full description

Hi there, here are Nadine & Robin, the two founders of nag. Most reminder apps remind you once and then give up. nag doesn't. It comes back, over and over, until you actually mark the thing as done. That's the whole idea. WHY WE BUILT IT We forgot things. Small things like paying a bill, taking a pill, redeeming a coupon. Recurring things like the compost, the laundry, drinking enough water. So we tried the reminder apps out there (more than a hundred of them sat on our phones) and we always hit the same two walls. First, they remind you once and then go quiet. A reminder arrives at a bad moment, you swipe it away, and it's gone for good. We wanted one that keeps coming until the job is done. A few apps could do it, but they gave up in endurance testing after a couple of weeks, so you could never really rely on them. Second, they are either bloated with features you never asked for, or so simple they break on a real repeat. We wanted an app that does a few things better than anyone else. So we built nag. We have been working on it with several people since 2019. Every reminder app can fire once. What separates them is the second reminder, and the fiftieth. The one you swiped away at a red light. The monthly one on the 31st. The yearly one in a leap year. Most apps quietly drop those, and you find out when it is already too late. We have spent seven years on exactly those cases. It is the least glamorous work in software, and it is the entire product. WHAT YOU GET Reminders that don't give up Firing once is easy. Coming back is the hard part. Every repeat is re-checked against a reference implementation before we ship a release, so your monthly reminder lands on the right day. An overdue nag comes back at the interval you choose, every 5 minutes, every 15, or hourly, until you tick it off. Postpone straight from the notification +10 minutes, +1 hour, +1 day, or done. The app stays closed. Repeats that hold From "every day at 7" to "every 3rd Monday of the second month". Monthly and yearly nags land on the right day, every time. Set a reminder in seconds Write it the way you would say it, or use the time picker with 12 presets you can change. Focus timer, logbook and widget Time a task, look back at everything you finished, and keep what's next on your Home Screen. Works fully offline You don't need internet to get reminded. Even after three weeks without a connection, your reminders fire as scheduled. No account needed nag works completely without one. Sign in with Apple or Google only if you want your reminders backed up and synced across devices. WHAT OUR USERS SAY "I really like that the app pings reminders several times, so if I miss the first, it keeps going. Instead of silently sitting in the notification tray." "I love it! It's on my home screen next to my calendar. Love that the reminders are simultaneously REALLY easy to make short ones, AND able to make detailed ones." "Awesome! Saved me from multiple alarms. My daughter and I both have ADHD and have such a difficult time remembering small details, so we were constantly forgetting keys, lunch, homework, meeting notes." SUBSCRIPTION nag comes with a free trial. It then continues as an auto-renewing subscription. The trial length and the price for your country are shown in the app before you buy, and you can cancel anytime in your App Store settings. No ads, no selling of your data. The subscription is what keeps nag running and bug-free for years. Terms of Use: https://nagreminder.com/terms Privacy Policy: https://nagreminder.com/privacy If you have questions, just write to us. We answer ourselves and we look forward to your message. All the best from Switzerland Nadine & Robin

About

ContactOne

This app helps you organize your contacts by finding and merging duplicates across various accounts like iCloud, Google, and Microsoft. It allows you to review all changes before they are made and offers an easy undo option. The app also tidies up inconsistencies in phone numbers and labels.

Highlights
  • Finds and merges duplicate contacts
  • Supports iCloud, Google, and Microsoft accounts
  • Review changes before merging
  • One-tap undo functionality
  • Cleans up phone number and label inconsistencies
  • Account-aware merging
Features
Read full description

Your contacts are a bit of a mess. That's okay. We'll sort it out together. ContactOne finds the duplicates, tidies the chaos, and cleans up every account, safely, so you never lose a number, a name, or that note you swore you'd remember. If your contacts have quietly piled up across iCloud, Google, Microsoft, and other accounts for years, you know the scene: the same friend saved three times, phone numbers in five different formats, half-empty cards, dead links, and a "John (New)" you haven't texted since 2019. ContactOne clears it all up, and shows you exactly what's happening before it touches a thing. FIND THE SNEAKY DUPLICATES You synced iCloud. Then Google. Then Microsoft. And somewhere along the way, everyone you know quietly multiplied. ContactOne's smart matching finds the copies, even when it's the same person hiding under a nickname, a maiden name, or a second number. And it's careful: two coworkers who just share an office line won't get mashed into one very confused contact. YOU'RE ALWAYS IN CHARGE Nothing merges until you say go. ContactOne lays every phone, email, address, and label side by side so you can pick the keepers with a tap. Every number, name, and note comes along for the ride. No more discovering months later that a mobile number quietly wandered off. IT ACTUALLY GETS YOUR ACCOUNTS Here's what most cleanup apps miss: your contacts don't live in one tidy pile. They're scattered across iCloud, Google, Microsoft, and more, each with its own quirks and rules. Lesser apps flatten them together and scramble your accounts. ContactOne knows exactly which account each contact calls home. It merges the right way, drops the result exactly where you want it, and respects what each account can actually store, so everything syncs back clean, no surprises. This account-aware engine is patent pending. TIDY UP THE LITTLE THINGS Duplicates are just the start. ContactOne also: • Straightens phone numbers into one neat, consistent style • Clears out dead and outdated website links • Sorts mismatched labels (Cell, Mobile, mobile... pick a lane) • Catches duplicate numbers and emails hiding inside a single card It spots these for you and suggests the fix. Just tap to tidy. NOTHING EVER GETS LOST. PROMISE. This is where other apps drop the ball, and your data. Every merge is saved safely and undoes with a single tap. Your originals are tucked away, so if you change your mind, they come right back, exactly as they were. Not sure two people are really the same? Keep them apart. ContactOne remembers, and won't nag you about it again. And because it's your data on the line, every release ships only after passing 500+ automated tests, so the app you trust with your contacts stays rock-solid. WHY YOU'LL LOVE IT • Finds the duplicates that hide, without merging people who shouldn't be • Actually understands your accounts (rarer than it should be) • You review everything; nothing happens behind your back • One-tap undo, always • A clean, complete address book that finally feels like yours Give your contacts the fresh start they've been begging for. Download ContactOne free, and enjoy scrolling to one tidy "Mom" instead of three. Available in English, French, German, Hindi, Italian, and Spanish. Looks right at home in both Light and Dark Mode. PICK HOW YOU PAY ContactOne is free to try, with 10 merges and 100 cleanups included. Go unlimited whichever way suits you: • Annual: $24.99 per year • Monthly: $4.99 per month • Lifetime: $39.99 once, yours forever, no subscription Annual and Monthly are auto-renewing subscriptions. Payment is charged to your Apple Account at confirmation of purchase. They renew automatically unless canceled at least 24 hours before the end of the period, and you can manage or cancel anytime in your Apple Account settings. Lifetime is a one-time purchase that never renews. Terms of Use (EULA): https://www.contactone.app/terms-of-use Privacy Policy: https://www.contactone.app/privacy-policy

Screenshots

nag4 screens
ContactOne4 screens

Verdict

The call

The clearest difference is review sentiment: ContactOne at 100% against nag's 50%. ContactOne also leads on rating (5.0 vs 3.0). On price, ratings volume, update cadence and ads there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. nag sells 5 in-app purchases, starting at $9.99 per 7 days and ContactOne sells 3 in-app purchases, starting at $4.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

ContactOne holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 2 and 1 respectively. Written reviews point the same way: 50% of nag's written reviews are positive against 100% of ContactOne's.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 2 days. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
nag versus ContactOne: the parameters behind the verdict, then further details
ParameternagContactOne
PriceFreeFree
Rating3.0 (2 ratings)5.0 (1 ratings) — better
Positive reviews50.0% of reviews100.0% of reviews — better
Number of ratings2 — better1
Update frequencyEvery 2 daysEvery 2 days
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, Apple WatchiPhone, iPad
Requires iOS17.017.0
Further details — not scored
Size113 MB9 MB
Age rating4+4+
DeveloperRobin KunzContactOne Inc.

Customer experience

nag

All ratings2 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

ContactOne

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews7 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

5 purchases

nag

Subscriptions4
  • nag Pro — Weekly$9.997 Days
  • nag Pro — Yearly3 Days trial$19.001 Year
  • nag Pro — Yearly3 Days trial$39.991 Year
Show 1 more
  • Annual Subscription14 Days trial$44.991 Year
One-time1
  • nag Pro — Lifetime$149.99
3 purchases

ContactOne

Subscriptions2
  • Monthly$4.991 Month
  • Annual$24.991 Year
One-time1
  • Lifetime Access$39.99

Questions

Is nag free?
nag is free to download, with in-app purchases available.
Is ContactOne free?
ContactOne is free to download, with in-app purchases available.
Which has better reviews, nag or ContactOne?
ContactOne is rated higher. nag averages 3.0 out of 5 from 2 ratings, while ContactOne averages 5.0 from 1 ratings.
Do nag or ContactOne have ads?
Neither nag nor ContactOne shows ads.
Which is updated more often, nag or ContactOne?
nag ships an update every 2 days, and ContactOne every 2 days. Most recently, nag was updated on October 30, 2026 and ContactOne on October 31, 2026.

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