Comparison

ちゃっとも vs UnderLine

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

Head to head
About

ちゃっとも

Connect with new people through group or one-on-one chats. Create or join groups based on shared interests and engage in lively conversations. Enjoy a simple, anonymous, and secure platform for making friends.

Highlights
  • Free to use
  • Group chat functionality
  • One-on-one private messaging
  • Anonymous user profiles
  • Interest-based groups
  • User reporting and blocking
Features
Read full description

◆ちゃっともとは◆ 完全無料で全ての機能が使える友達作りチャットアプリです! グループトークで盛り上がろう! グループを作成して、趣味や話題ごとにみんなでワイワイ会話。 他にはないグループチャット機能が人気の秘密! 1対1チャットで気が合う友達と 気になる人を見つけたら、個別メッセージでじっくりトーク。 お気に入り機能で仲良くなった友達をキープ! カンタン・匿名・安心 ニックネームを入力するだけで即スタート。 メールアドレスや電話番号の登録は一切不要! ◆こんな人におすすめ◆ ・暇な時間にサクッと友達と話したい ・同じ趣味の仲間を見つけたい ・学生同士、社会人同士で気軽に雑談したい ・グループで盛り上がる場所がほしい ・匿名で安心して使いたい ◆安心・安全の取り組み◆ ・24時間モニタリング体制 ・不適切なユーザーの通報・ブロック機能 ・出会い目的の利用禁止(利用規約で明記) ◆注意事項◆ 以下の行為はサービスの利用停止の対象となります。 ・個人情報や連絡先の交換 ・直接の出会いを目的とした利用 ・卑猥・過激なメッセージ、画像の投稿 ・勧誘、宣伝目的の利用 ・誹謗中傷

About

UnderLine

Features
Read full description

UnderLine is a one-to-one messaging app that lets your conversation partner see your words in real time while you type. Unlike conventional messaging apps, where the other person sees your words only after you tap Send, UnderLine lets the conversation begin from the moment you start typing. When you delete draft text, the change is also reflected on the other person's screen. This makes it possible to share the rhythm of a conversation and the way words take shape, even when you are apart. Key features - Real-time display of text while it is being typed - Simple one-to-one messaging - Add friends using public IDs or QR codes - See in your conversation list when someone is typing - Search your contacts, and your conversation list by name or message - Mute notifications, pin conversations, or hide them from your list - Push notifications for new messages - Blocking, reporting, and in-app account deletion - Encrypted device-to-device transfer using a QR code - Encrypted iCloud backup and restoration Message bodies and live-typing text are end-to-end encrypted. Push notifications never include message content. Important notes - Live typing is visible while the other person has the same conversation open. Because text may be seen before you tap Send, do not type anything you do not want the other person to see. - Enable notifications to receive new-message alerts while the app is in the background or closed. Message content is not shown in notifications.

Screenshots

ちゃっとも3 screens
UnderLine4 screens

Verdict

The call

The clearest difference is ads: UnderLine at none against ちゃっとも's shown. UnderLine also leads on iOS requirement (15.6 vs 17.0). On price, update cadence, in-app purchases 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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

ちゃっとも ships an update every 3 days, UnderLine every 2 days. The most recent releases landed on November 3, 2026 and October 30, 2026 respectively.

Scorecard2 real differences · 7 level
ちゃっとも versus UnderLine: the parameters behind the verdict, then further details
ParameterちゃっともUnderLine
PriceFreeFree
Rating4.7 (16 ratings) — better—
Number of ratings16 — better—
Update frequencyEvery 3 daysEvery 2 days — better
AdsYesNo — better
In-app purchasesNoNo
MonetizationAd-supported—
DevicesiPhone, iPadiPhone, iPod
Requires iOS17.015.6 — better
Further details — not scored
Size37 MB67 MB
Age rating17+17+
DeveloperONETT5mm

In-app purchases

None

ちゃっとも

No in-app purchases

None

UnderLine

No in-app purchases

Questions

Is ちゃっとも free?
ちゃっとも is free to download, with no in-app purchases.
Is UnderLine free?
UnderLine is free to download, with no in-app purchases.
Do ちゃっとも or UnderLine have ads?
ちゃっとも shows ads; UnderLine does not.
Which is updated more often, ちゃっとも or UnderLine?
ちゃっとも ships an update every 3 days, and UnderLine every 2 days. Most recently, ちゃっとも was updated on November 3, 2026 and UnderLine on October 30, 2026.

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