Comparison

MAMORIO vs Kotodute

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

Head to head
About

MAMORIO

This app helps you prevent losing your belongings by attaching a small tag. It notifies you when you leave an item behind and allows you to see its last detected location via a Bluetooth crowd-sensor network. It also offers a community-based finding feature and lost-and-found integration in select regions.

Highlights
  • Left-behind alerts
  • Last detected location history
  • Crowd tracking network
  • MAMORIO Spot integration (Japan)
  • iPhone found alerts (Japan)
  • Tag setup and management
Features
Read full description

A modern charm for your keys and wallet. MAMORIO is the official app for the lost-item prevention tag that lets you trace "when and where" your belongings were last seen. Not GPS — a Bluetooth crowd-sensor network. That's why MAMORIO is thin, light, and long-lasting on battery. Comfortable to keep on your keys or in your wallet, all year round. What this app does - Set up and manage your MAMORIO tags in minutes - Notify you the moment your tag is out of range (left-behind alert) - Show the last detected place and time on a map (history, not real-time tracking) - Turn "Find with Everyone" (crowd tracking) on or off - Receive alerts from MAMORIO Spot stations (Japan only) - Get an email if your iPhone itself reaches a partnered lost-and-found center ■ Left-behind alerts, the moment it matters The moment your iPhone stops detecting your MAMORIO, you'll get a notification. A small heads-up before you leave the table, the train, or the meeting room prevents most forgotten items. ■ Trace "when and where" — on a map View the last place and time your MAMORIO was detected. MAMORIO does not stream a live location. It records each detected moment as history, so you can retrace where it might be. ■ Find with Everyone — crowd tracking (Patent No. 5894309) A unique feature that uses the network of MAMORIO users to quietly search for your missing item. When your MAMORIO is not nearby, a "Find with Everyone" button appears. Turn it on, and whenever another MAMORIO user passes near your tag, the place and time are sent to your app. * No information about your MAMORIO is shared with other users. ■ MAMORIO Spot — partnered lost-and-found counters (Japan only) In Japan, major train stations and commercial facilities are equipped with MAMORIO Spot devices. When a missing MAMORIO arrives at a Spot, the location is delivered to your app. The current list of partnered centers is available in-app. (Requires "Find with Everyone" to be on. This feature is currently available in Japan only.) ■ When your iPhone itself is found (Japan only) If the iPhone running this app is turned in to a partnered lost-and-found center in Japan, you'll receive an email at your registered address. You can use this feature even without owning a MAMORIO tag. * Configuration via the app or web is required. The list of partnered centers is available in-app. Currently limited to Japan. Before you start ■ There is no GPS chip inside MAMORIO MAMORIO records a history of "when and where" your item was detected. It cannot stream the live position of an item that has left your side. In return, MAMORIO is remarkably thin, light, and long on battery life. It is not suitable for real-time tracking of children, pets, or elderly family members. ■ About location data Location is obtained via your iPhone's GPS and network signals. Accuracy may vary by signal conditions and environment. For background detection, we recommend setting Location to "Always Allow". ■ Effective range (Bluetooth) Communication range varies by product model and can be shortened by walls, crowds, or interference. [Specifications] Wireless: Bluetooth Low Energy URL scheme: mamorio:// A quiet, watchful Bluetooth network. A modern charm for the keys and wallet you'd rather never lose.

About

Kotodute

Features
Read full description

Do you have words you want to leave behind for someone you love? Kotodute is an app that delivers your heartfelt messages to the people who matter most, when you no longer can. Create a message for one loved one free forever. Upgrade with a one-time purchase to create up to 10 messages—no monthly or yearly subscription. Kotodute checks in with you once a month. Your message is delivered only if you stop responding, helping ensure it is sent only when truly needed. Leave your unspoken words in safe hands, and let them reach the future. FEATURES ■ One Message Free Forever Create and keep one message for a loved one at no cost. Upgrade with a one-time purchase to create up to 10 messages. No subscriptions. No recurring fees. ■ Your Data Stays Yours Kotodute has no developer-operated server. Your messages, recipients, and settings are stored only in your own Google account. No one—including the developer—can view or access your messages. Your memories remain under your control. ■ Messages Are Sent from Your Gmail Messages are never sent from our servers. If delivery becomes necessary, they are sent directly from your own Gmail account. Recipients receive the message as if it came directly from you. ■ Monthly Check-ins Help Prevent Mistakes Once a month, simply confirm that you're okay. As long as you continue checking in, your messages will never be sent. If a check-in is missed, reminder emails are sent first to reduce the risk of accidental delivery. ■ Simple Setup 1. Write your message. 2. Choose the recipient. 3. Check in once each month. That's all. WHO IS IT FOR? • Anyone who wants to leave a message for loved ones • People who want to express gratitude to family • Those who want to leave words for a spouse or partner • Parents who want to leave messages for their children • Anyone preparing for the future, one step at a time • Anyone who wants peace of mind FREQUENTLY ASKED QUESTIONS Q. Is the app free? A. Yes. One message for one loved one is free forever. A one-time purchase unlocks up to 10 messages. Q. Is there a subscription? A. No. Kotodute uses a one-time purchase. There are no monthly or yearly fees. Q. Where are my messages stored? A. Everything is stored only in your own Google account. No one—including the developer—can access your data. Q. Who sends the messages? A. Messages are sent from your own Gmail account, never from a company server. Q. When are messages delivered? A. If you do not complete your monthly check-in, messages are scheduled to be sent on the first day of the following month. If you have designated a trusted contact, they will first receive an email asking them to confirm your well-being. Messages are sent only if no response is received within 48 hours. Q. How do you prevent accidental delivery? A. Kotodute requires a monthly check-in and sends reminder emails before any delivery. Multiple confirmation steps help minimize accidental sending. Q. Why do I need a Google account? A. Your data is never stored on our servers. Everything stays securely in your own Google account, ensuring only you control your messages. Q. Do recipients need the app? A. No. They receive a normal email and do not need to install Kotodute. Q. Do I need the app to edit my messages? A. Yes. Editing messages requires the Kotodute app. Q. Does Kotodute support widgets? A. Yes. You can complete your monthly check-in directly from a widget without opening the app. The words you leave behind may become a lifelong treasure for someone you love. Kotodute helps deliver the words you couldn't say, even when you're no longer able to say them yourself.

Screenshots

MAMORIO3 screens
Kotodute4 screens

Verdict

The call

The clearest difference is iOS requirement: MAMORIO at 15.0 against Kotodute's 18.0. On price, update cadence, ads and in-app purchases 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. MAMORIO sells 4 in-app purchases, starting at $8.99 per year and Kotodute sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

MAMORIO ships an update every 10 days, Kotodute weekly. Both last shipped on October 24, 2026.

Scorecard1 real difference · 9 level
MAMORIO versus Kotodute: the parameters behind the verdict, then further details
ParameterMAMORIOKotodute
PriceFreeFree
Rating4.0 (3 ratings) — better—
Positive reviews25.5% of reviews—
Number of ratings3 — better—
Update frequencyEvery 10 daysWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better18.0
Further details — not scored
Size63 MB12 MB
Age rating4+4+
DeveloperNEARIZE K.K.Toshinori Matsui

In-app purchases

4 purchases

MAMORIO

Subscriptions4
  • Anshin Plan(wallet)$8.991 Year
  • AnshinPlan(Bag)$8.991 Year
  • Anshin Plan(Key)$8.991 Year
Show 1 more
  • Anshin Plan(Electronics)$8.991 Year
1 purchases

Kotodute

One-time1
  • Kotodute Premium$5.99

Questions

Is MAMORIO free?
MAMORIO is free to download, with in-app purchases available.
Is Kotodute free?
Kotodute is free to download, with in-app purchases available.
Do MAMORIO or Kotodute have ads?
Neither MAMORIO nor Kotodute shows ads.
Which is updated more often, MAMORIO or Kotodute?
MAMORIO ships an update every 10 days, and Kotodute weekly. Most recently, MAMORIO was updated on October 24, 2026 and Kotodute on October 24, 2026.

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