CSipSimple is described as 'Csipsimple will allow native sip for android device' and is a Video Calling app in the social & communications category. There are more than 10 alternatives to CSipSimple for a variety of platforms, including Android, iPhone, Windows, Mac and iPad apps. The best CSipSimple alternative is Jami, which is both free and Open Source. Other great apps like CSipSimple are Jitsi Desktop, Linphone, Zoiper and MicroSIP.
Jami (formerly GNU Ring, SFLphone) positions itself as a potential free Skype replacement
Jami is the most popular Windows, Android, Mac & iPhone alternative to CSipSimple.
Jami is the most popular Open Source & free alternative to CSipSimple.
Jitsi Desktop (previously SIP Communicator) is a legacy audio/video and chat communicator with full encryption, precedessor of Jitsi Meet .
Jitsi Desktop is the most popular Web-based & Self-Hosted alternative to CSipSimple.
Linphone is one of the most famous open source softphones in the world. It is fully SIP-based, for all calling, presence and IM features.
Open Source SIP Voip client that is actively maintained.
Most users think Linphone is a great CSipSimple alternative.
Zoiper IAX & SIP multilanguage and multiplatform (Windows, Linux and Mac OS X) softphone is a VoIP soft client, meant to work with any IP-based communications systems and infrastructure.
MicroSIP is a free portable SIP softphone for Windows based on PJSIP stack. It allowing to do high quality VoIP calls (P2P or on regular telephones) via open SIP protocol. From cloud of SIP providers you can choose best for you, register account and use it with MicroSIP. You'.
I love MicroSIP, but it's Windows only, while CSipSimple is Android.
Talkatone gives you free calls, text messages, real-time location sharing and picture sharing to Facebook and Google friends, or any phone number in US.
With a superbly designed and intuitive user interface, the softphone offers easy set up with lots of preconfigured VoIP providers built in and smart call management features. Enjoy high quality enterprise communication features with zero effect on battery life.
SessionTalk SIP Softphone is the most popular commercial alternative to CSipSimple.
PhonerLite enables your PC to use it for internet telephony (VoIP , Voice over IP, SIP). You need an internet connection and an account from a provider supporting the SIP protocol.
Sipnetic is a free VoIP softphone based on the SIP protocol. Sipnetic supports voice and video calls, instant messages, presence information and end-to-end encryption.
Nice UI, Compatible with latest Android versions, App is in active development
MizuDroid is an unlocked VoIP softphone for Android mobile phones and tablets based on open standards, compatible with all VoIP providers, software and devices using the SIP protocol.
Canada
United States
France
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Bulgaria
United Kingdom
Estonia
Romania
Jitsi Meet for Android, at least, cannot be configured as a sip client - it only has one entry - "https server" - and that's it.