# CosmoSia — Easy to use and full support!

> Personalized email address creation and management with enhanced privacy. (iPhone/iPad app by ACCESS CO., LTD..)

- Source: https://appshunter.io/ios/app/cosmosia/id1566565605 (this page in markdown: same URL + `.md`)
- Developer: [ACCESS CO., LTD.](https://appshunter.io/developer/364885144)
- Category: Productivity, Utilities
- Price: Free with in-app purchases
- Rating: 1.00/5 from 1 App Store ratings · 39 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.0 · 219 MB
- Languages: American English, Japanese
- Released: 2021-08-12
- Data updated: 2026-08-26
- Monetization: free with in-app purchases
- User reviews in markdown: https://appshunter.io/ios/app/cosmosia/id1566565605/reviews.md

## What is CosmoSia?

Recommended for those who are considering moving away from carrier email.
You can create "XX@cosmosia.email" which is as easy to use as your carrier email!
Made in Japan, so you can be sure of your privacy.
 
Make your email more fun! The long-awaited iOS version of the free email app with over 1 million users is now available!


- Just tap! The all-new "Reactions" feature
Get your feelings across without words: Just like in a chat, react to emails with emoji.

Reaches the other person even without the app: When you add a reaction, the recipient automatically receives a clear notification email. No matter which email service they use — Gmail, docomo mail, Yahoo! Mail, and more — your "I saw it" comes through loud and clear.

Stay connected like a conversation: Even in group exchanges, you can see at a glance who reacted and how, so conversations keep flowing and stay fun.


- You can create your own email address!
You can create your own e-mail address such as XX@cosmosia.email.
You can use email addresses such as XX@cosmosia.email. The email address will be linked to your phone number like a carrier email address, so please consider this when you are thinking of moving from a carrier email address!
Email address is available only when you purchase the subscription "CosmoSia Email Plan (Monthly)".
We also recommend this service when you move to ahamo, povo, LINEMO, or other plans that do not include carrier email!
====================
 
- You can manage multiple email services at once.
IMAP4 (Gmail, docomo mail, etc.) is supported.
　
- It is a standard email application for low-cost smartphones and MVNOs.
It's easy to use, just like a carrier email, and it's popular among low-cost smartphone users!
 
- Easy to set up
Just set your email address and password and you're ready to go. Organize your mailbox now.

- No more unwanted e-mails!
We support a "reject list" function that allows you to prevent unwanted e-mails from entering your inbox.

- Basic functions are free!
The installation is free and the basic functions are free no matter how many times you use them.
A predetermined usage fee is required to use CosmoSia Mail.
You will have to pay for the communication charges incurred when sending and receiving emails.
 
====================
The following email services can be used
docomo mail 
au-mail
R mail
Y! mobile mail
Yahoo! JAPAN mail
iCloud mail
Gmail
Outlook/Hotmail
mineo mail
so-net mail
BIGLOBE mail
We support the setup of many other email services.

* You cannot use your UQ mobile email address (XX@uqmobile.jp).
Please look forward to future updates for support of other mail services!
====================

About the trademark
docomo mail is a trademark of NTT DOCOMO, INC. in Japan.

## Key features

- Create custom email addresses
- Manage multiple email accounts
- Block unwanted emails
- Easy setup
- Carrier-like usability
- Privacy-focused

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| CosmoSia Mail Plan(Monthly) | $2.99 | per month |


## Recent user reviews (10 of 39)

All indexed reviews: https://appshunter.io/ios/app/cosmosia/id1566565605/reviews.md

### 3/5 — メールが受信されません

*2025-07-12, version 1.9.1*

ある日を境に"受信失敗"と通知が届くようになり更新ボタンを押しても改善されず、それどころか過去のメールも確認することが出来なくなりました。対応お願いします。

### 1/5 — Gmailで使えない

*2025-05-24, version 1.8.0*

Gmailのアカウントを登録しようとすると、「このアプリはブロックされます　
このアプリが、Google アカウントのプライベート な情報にアクセスしようとしました。アカウント を安全に保つため、Googleによりこのアクセスは ブロックされました。」と表示されて使えません。

### 3/5 — So-netメール設定ができない

*2025-04-29, version 1.8.0*

So-netのメールアカウントを追加しようとすると受信サーバーへの接続に失敗したと表示され設定ができない
その他のメールから設定してみても駄目だった
と言うかその他のメール設定があるなら細かく手動で設定できるようにしてくれないと何も解決しない

### 1/5 — プッシュで来なかった

*2025-01-30, version 1.8.0*

プッシュ受信が出来ると謳っていたのに、2日分くらいがまとめて来ました。
どうして？

### 3/5 — AndroidからiPhone

*2024-09-10, version 1.8.0*

先日iPhone版を使い始めました。振り分け登録後に自動で振り分けてくれるのはとても助かります。
しかしながら、既読を付けるのにも削除するにも「全て選択」の項目が無く、一つずつ選択しなければならないのが苦痛です。よくある質問で調べても分かりませんでした。
同じアプリなのにAndroidとiPhoneでここまで仕様違う？と思ってしまいました…。
振り分け登録はとても良い機能なので継続して使いたい所ですが山のようにDMが溜まっていくのが目に見えているので継続を悩んでます。

### 1/5 — ゴミ箱にあるメールを一括で選択削除できない

*2024-07-05, version 1.8.0*

ゴミ箱にあるメールを一括で選択削除できない。
1000件オーバーのゴミ箱のメールを1つ1つ選択して削除しなければならないなんて現実的じゃないです。
ほんと使えないです。

### 1/5 — 使えない

*2024-06-24, version 1.8.0*

gmail設定しようとしたら、Googleポリシーに反する為ブロックしましたと出て設定できない。なんで?

### 3/5 — アプリが落ちまくる

*2024-05-14, version 1.8.0*

メールを開いて削除するだけでアプリが落ちることが多い。30分くらい試用してみて6回くらい落ちた。安定性に問題がありそう。また、ゴミ箱を空にしたいのにいちいち選択しないといけないのも地味にストレス。mineoメールがサーバー設定せずに使えるのは非常に良い。

### 1/5 — SMS、チャット風にはならない

*2024-05-03, version 1.8.0*

どこを探してもSMS風、チャット風への切り替えるメニューがなく、公式に謳っているデザインの変更などもできない。
課金ゾーンかなと思ったけど、公式サイトでは無料プランでSMS風、チャット風に切り替えができる！と明記してあり、無駄な時間を費やした。
AndroidやPC限定ならそう書いておいて欲しい。個人情報が大切な時代にこのアプリと連携してよかったのかすら心配になった。
私の求める条件がそもそもなかったため、メーラーとしての良し悪し評価しないが、他の人のレビューや更新の頻度を見るに、まあそうなんどろう。

### 1/5 — どうして？

*2024-01-03, version 1.8.0*

本文が表示されません
どうしてなんでしょうか？

## Frequently asked questions about CosmoSia

### What does CosmoSia do?

CosmoSia allows you to create and manage your own personalized email address, such as 'XX@cosmosia.email'. It offers a user-friendly interface similar to carrier emails and supports managing multiple email services like Gmail and Outlook.

### What are the key features of CosmoSia?

Key features include the ability to create your own email address, manage multiple email accounts from various providers (IMAP4 supported), an easy setup process, and a reject list function to block unwanted emails. The app is made in Japan, emphasizing privacy.

### How much does CosmoSia cost?

The app itself is free to install and basic functions are free to use. However, a subscription plan called 'CosmoSia Email Plan (Monthly)' is required to use your custom '@cosmosia.email' address. Communication charges for sending and receiving emails will also apply.

### What devices is CosmoSia compatible with?

The description specifically mentions an iOS version is available. While not explicitly stated for Android, it's common for such email management apps to support both major mobile operating systems. Users should check their respective app stores for compatibility.

### Who would benefit from using CosmoSia?

This app is recommended for individuals considering moving away from carrier email, those looking for a more professional or personalized email address, users of low-cost smartphones and MVNOs, and anyone who wants to manage multiple email services in one place with enhanced privacy.

## Version history (last 5 releases)

### 1.10.3 — 2026-08-20

Introducing "Reactions"! Make replying to emails easier and more fun. Send a quick "Got it," "Confirmed," or "Thanks" to the other person with a single tap — no need to write out a message. Backed by our proprietary patented technology (patent granted), it lets you expand your circle of communication safely and securely.

### 1.10.2 — 2026-08-12

Introducing "Reactions"! Make replying to emails easier and more fun. Send a quick "Got it," "Confirmed," or "Thanks" to the other person with a single tap — no need to write out a message. Backed by our proprietary patented technology (patent granted), it lets you expand your circle of communication safely and securely.

### 1.10.1 — 2026-08-05

Fix some bugs.

### 1.10.0 — 2026-07-29

Fix some bugs.

### 1.9.2 — 2025-07-15

Fixed some bugs.

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## More apps by ACCESS CO., LTD.

- [SIGNESS player](https://appshunter.io/ios/app/signess-player/id629918493)
- [PUBLUS Lite](https://appshunter.io/ios/app/publus-lite/id878032908)
- [Linkit](https://appshunter.io/ios/app/linkit/id886548766)
- [Palmap](https://appshunter.io/ios/app/palmap/id6451233679)

All apps by ACCESS CO., LTD.: https://appshunter.io/developer/364885144

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-26.*