Overview

Blink is a SIP-based communications client for people who want voice and video calls alongside messaging, file transfers, screen sharing, and conferencing. Its breadth is appealing for individuals and teams already working with SIP, but it is not a calling service: using the client requires a SIP account.

For a free desktop client with several communication modes and encryption options, Blink is worth considering. The trade-off is that features vary by operating system and version, and some conference functions need a conference server.

Compare it with other options in Softphone Software.

Key features

Calling and conferencing

Blink supports Opus audio, H.264, VP8, and VP9 video, with acoustic echo cancellation and ZRTP media encryption. That combination gives SIP users a broad set of voice and video capabilities in one client. Screen sharing can accompany audio, and conferences can combine VoIP, messaging, presence, file transfers, and screen sharing, with participant management. Organizations should account for the conference-server requirement for some functions.

Messaging, transfers, and security

Chat sessions use MSRP, with OTR encryption support, SIMPLE presence, and XCAP server storage. File transfers use MSRP over TLS and include progress reporting and delivery confirmation. OpenPGP messaging support adds another security option. These tools make Blink more than a dialer, though encryption methods differ by activity rather than being one uniform protection layer.

Accounts and contacts

Users can manage multiple SIP accounts, sync accounts between computers through iCloud, or sign up for a SIP2SIP account within Blink. Contact sources include the system address book, LDAP search, Bonjour neighbours, and web pages showing caller information. SIP2SIP sign-up can lower the friction of getting started, but the account requirement remains central to using the client.

Pricing

Blink: Free. The plan provides Linux, Mac, and Windows downloads, but requires a SIP account. It suits users who already have SIP service or are prepared to obtain an account; the free client price does not remove the need for that service.

Blink Pro: custom pricing. Discounted pricing is available for organizations with more than 100 seats, and AG Projects can provide demonstrations and support integrating Blink for those organizations. This is the relevant route for larger deployments seeking integration assistance, while smaller teams have no stated Pro price to weigh against the free client.

Platforms

Blink is associated with Android, iOS, Linux, macOS, web, and Windows. Its download page offers Mac, Windows, and Linux versions, with Debian and Ubuntu installation instructions. Since features can vary by operating system and version, users should confirm that the functions they need are supported on their intended platform. Browser calling and mobile and desktop apps are indicated, as is call recording.

Who it's for

Blink fits SIP users who want calling, chat, file exchange, and conferencing in one client, particularly organizations with more than 100 seats that may benefit from integration support. It is less suited to someone looking for a standalone phone service without arranging an account, or to teams that need conference functions without a conference server.

Pros and cons

Pros: The free plan covers Linux, Mac, and Windows, making it a low-cost client choice for people with SIP service.
Pros: Calling, messaging, file transfer, and screen sharing can be combined in conferences, reducing the need to split these activities across separate tools.
Pros: ZRTP, OTR, TLS, and OpenPGP support address media, chat, transfer, and messaging security needs.
Cons: A SIP account is required, so Blink alone does not provide calling access.
Cons: Feature variation by platform and version, plus conference-server dependencies, complicates planning for teams with specific requirements.

Alternatives

Choose Linphone if open-source software, project integration under GNU GPLv3, or its wider range of listed platforms—including self-hosted and API options—is a priority; proprietary licensing is also available for closed-source projects.

Siperb Mobile Softphone is another freemium option with a Personal plan at no cost, but that plan has limited storage, seven-day SIP Trace and Register Activity logs, community support, and no technical support.

Consider SipPulse Softphone if its App SipPulse plan, priced free for iOS, Android, Windows, and Linux with unlimited users and installations, better matches your deployment needs.

Zoiper offers a free non-commercial desktop softphone plan capped at one account and two lines, so it may suit personal use with modest account needs.

For a paid team phone option, SessionTalk Softphone offers Teams Phone at 20.00 USD per month, with five seats included, $3 per extra seat, and a $20/month logo-branding add-on.

Softphone.Pro is a trial-available alternative with selectable monthly or annual billing and subscription terms of one, six, or twelve months.

Pick Browser Phone if a free, open-source, self-hosted web option is the priority.

AGEphone is another freemium option for Windows, iOS, and Android.

Verdict

Blink is a strong fit for SIP users who want a free client that brings secure messaging, transfers, screen sharing, and conferencing together with voice and video. Its main limitation is practical: users must bring a SIP account, and conference capabilities depend in part on platform support and server setup. Choose Blink if that infrastructure is already in place; look elsewhere if you need an all-in-one calling service or more predictable conference requirements.

	Blink	Sip:phone
Free plan	Yes
Paid from	Free
Platforms	Android, iOS, Linux, macOS, Web, Windows	iOS, Android
Free plan	Yes
Browser calling	Yes
Mobile app	Yes	Yes
Desktop app	Yes
Call recording	Yes
SIP support	Yes	Yes

Blink vs Sip:phone

Blink

Sip:phone