ICQ

Private messaging and VoIP for Windows

ICQ is a Windows messaging app built around private chats, voice calls, video calls, and large group communication. Its identity system is a little different from many modern messengers: you use a phone number to get a five-digit UIN, and you can keep details such as your name or phone number hidden from other users.

For everyday use, ICQ covers the essentials well. You can send one-to-one messages, create group chats, share photos, videos, GIFs, stickers, and use smart reply suggestions to answer faster. It also includes audio-to-text, which is useful if you prefer speaking a message but want to send it as text. The interface is user-friendly, and the large selection of emojis, animations, and stickers gives conversations a more casual feel.

Privacy is one of ICQ’s stronger points. Voice and video calls are encrypted using a ZRTP-based system, and messages can be deleted at any time, including from the other person’s chat. The app is cloud-based, so conversations can sync across devices. You can also message yourself, which works as a handy temporary place to keep media or notes, though it should not be treated as a full cloud storage service.

ICQ also supports larger communities. Group chats can include up to 25,000 participants, video calls can include up to 50 users, and groups can use polls and read indicators. Channels let users publish text posts with media attachments, while bot support gives businesses or advanced users a way to automate replies or provide information.

The main drawback is reach. ICQ has many useful features, but it does not have the broad user base of the most widely used messaging platforms, so its value depends on whether your contacts or community are willing to use it. It is best suited to users who want a privacy-minded messenger with group tools, calling, channels, and flexible identity controls.