csipsimple01CSipSimple is a free and open source SIP softphone available for Android mobile phones and tablets. Because of the open source license, CSipSimple is free to download, use, and modify.

Note that CSipSimple is not a Ringfree product. Because of this, we’re limited in the degree of support that we can provide for the application, however we’re happy to provide setup assistance. Because CSipSimple is a small open source project, there are no premium support options and what support is available is provided on a volunteer basis via a Google Group. You can find the group by clicking here.

It’s important to know that if you have Ringfree telephone service, you have an extension within your phone system. In order to prevent conflicts between CSipSimple (or another softphone) and your desk phone, a clone of your extension will need to be created. To create the cloned extension, simply contact Ringfree’s technical support.

It’s also worth noting that some cellular carriers, notably Verizon, block SIP traffic on the default port used by CSipSimple and other softphones. This effects softphone use on the carrier’s mobile data network but has no effect while using a WiFi connection. To circumvent this, Ringfree will need to open an auxiliary port for SIP traffic. Please indicate your cellular carrier when communicating with Ringfree’s technical support.


CSipSimple Mobile Application Setup

csipsimple03Begin by installing the CSipSimple app from the Google Play Store on your Android device.

Once CSipSimple has been installed, proceed to open the application. The first time you open it, a popup labeled Easy configuration will appear with some configuration options

Your personal preference as to the use of your device will dictate your choice for the field labeled Integrate with Android.

For the Availability profile we recommend setting this to Always available.

For the Mobile data availability option, we recommend checking the box labeled I’m allowed to use mobile as this will allow the app to work on your carrier’s mobile data network in addition to WiFi.

csipsimple05The next screen you see will prompt you to add an account. Tap the button to do so. This will open a popup labeled Choose wizard. Scroll down and in the section labeled Generic wizards select the option labeled Advanced.

On the next screen, note the fields labeled:

  • Account name
  • Server
  • Username
  • Password
  • Proxy

In the field labeled Account Name, enter something to identify the account should you enter additional accounts int he future. Normally “Ringfree” is a suitable option.

In the field labeled Server, please enter the following:


In the field labeled Username, please enter the number of the extension you would like associated with your CSipSimple installation. Normally this will be the cloned extension mentioned above rather than your normal extension number. You may contact Ringfree technical support or your IT provider if you have questions as to what to put here.

For the Password field, please consult with your IT provider or with Ringfree technical support.

In the field labeled Proxy, please enter the following:


csipsimple06Once all of the above has been entered, press the button labeled Save toward the bottom of the screen. You how have completed the steps necessary to configure CSipSimple on your Android device. If there are no errors with the configuration options, you should see a green bar underneath a gear icon as the Account name from above also listed in green.

Press the Back button to go to the dialer. You can now make and receive phone calls from your Android device using your Ringfree VoIP telephone service.