S.i vs Couple Calendar
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
S.i
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S.i(エスアイ)の公式アプリです。 【概要】 ■アプリ上から24時間いつでも予約が可能 指名予約にも対応しているので担当スタッフのスケジュールを確認してからの予約が可能です。 ■クーポン お得なクーポンが配信されます。ネット予約時にクーポン利用での予約も可能なので来店時もスムーズに施術頂けます。 ■スタッフが施術したギャラリーを掲載 前もって画像を確認しておけばスムーズなオーダーが可能です。 ■マイページ機能 予約状況の確認やキャンセルがマイページ上から行えます。スタッフの登録が出来るので前もって担当者を登録しておけばマイページからスムーズな指名予約が可能です。
Couple Calendar
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Couple Calendar is an app for couples to share events and avoid miscommunication. With just a few simple steps, you can share plans easily and make sure nothing gets missed. You can also check how many days you have been together and count down to your next date, making the time you spend together feel visible and meaningful. ■ Manage & Share Events - Share the same calendar and see each other's events in real time - Add, edit, or delete events and reflect changes for your partner right away - Filter events by participant ■ Quick Add with Templates - Save frequently used events as templates - Add events instantly with one tap - Easily add dates and recurring events ■ Organize Events with Labels - Add labels to events to keep your calendar easy to read - Categorize events by purpose for easier planning - Use colors to understand your calendar at a glance ■ Note Features - Use Count to see how many days are left until your next date - Use Day Count to automatically track how many days you have been together - Manage shopping lists and to-dos with checklists ■ Stamps - Add events with one tap using stamps - Reduce typing and add plans more smoothly ■ Messages - Coordinate plans with your partner through Messages - React to messages with stamps ■ Counter Notes (Premium) - Count events by event name or label - Track the total time spent on events - Visualize how much time you have spent together ■ Premium Features - Remove Ads - Unlock Premium Stamps - Unlock Event Search - Unlock Counter Notes - Unlock Widgets Terms of Use: https://www.card-chicken.jp/page/couplecalendar-terms-en
Screenshots
Verdict
The clearest difference is in-app purchases: S.i at none against Couple Calendar's 1. S.i also leads on iOS requirement (13.0 vs 26.0). Couple Calendar's advantage is update cadence (every 6 days vs every 48 months). On price, ads and device support 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
Both are free to download. Couple Calendar sells 1 one-off in-app purchase. S.i asks for nothing beyond the download.
S.i ships an update every 48 months, Couple Calendar every 6 days. The most recent releases landed on September 12, 2026 and September 13, 2026 respectively.
| Parameter | S.i | Couple Calendar |
|---|---|---|
| Price | Free | Free |
| Update frequency | Every 48 months | Every 6 days — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 13.0 — better | 26.0 |
| Further details — not scored | ||
| Size | 3 MB | 31 MB |
| Age rating | 4+ | 4+ |
| Developer | TATSUHIRO INOUE | Takuro Yoshizawa |
In-app purchases
S.i
No in-app purchases
Couple Calendar
- Koibito Calendar Premium$6.99






