PrivateGSM 9.06(r1541)

New Features

• Audio quality during secure call is kept at a constant good level, due to a compensation mechanism that slightly increase latency in order to avoid "gaps" in the speech, due to bad or intermittent network connection.
• Address book integration: after the secure call setup, two words (SAS: Short Authentication Strings) are shown on each phone display. Caller and called must verify that SAS are equals on both devices, in order to ensure that nobody is wiretapping the call. After the first verify, the two peers can set each other as verified and vice versa (marked as trusted), so that the SAS check it will not be required during the next call.
• While in a secure call, antenna icon will change color and shape to reflect the network quality.
• After installing PrivateGSM, the user will receive an SMS which summarizes the pre-requisites required for proper functioning.
• Resellers and support operators can now activate a PrivateGSM license even without inserting a SIM.

User interface improvements

• Application language can be changed in settings menu.
• Languages available:

• bulgarian
• brasilian
• finnish
• danish
• norvegian
• swedish

Network related improvements

• During the application startup, the phone is automatically configured in 2G mode.
• If the user is roaming abroad, there could be problem in setting up a secure call, due to different networks parameter. PrivateGSM suggests the user to start an automatic wizard to try different network configuration until it finds the best one suited for the local mobile operator.

Security improvements

• ZRTP implementation updated to protocol version 1.10.
• Address book integration allows the use of ZRTP pre-shared keys feature, make the time required to setup a secure call faster (improvement of 3 seconds).

Defects fixed

• Display rotation in landscape mode has been disabled (eg: E66, N95), since it can produce gaps in speech and in some cases (E90) call interruption

Compatibility note

This version of ZRTP protocol (1.1) is NOT compatible with the older one (0.90). It is not possible anymore to establish a secure call with a user who uses an older version. The older version should be upgraded in order to be able to connect a secure call with the new one. This situation is automatically detected on the device having the newer version and after the call has been hung up, the user is offered an option to send an upgrade invitation SMS to the other party having the outdated version.

PrivateGSM 9.05(r1152)

Defects fixed

• Minor bug on the previous releas fixed (battery problem).

PrivateGSM 9.04(r1004)

User interface improvements

• Call customer service from PrivateGSM Options Menu. Selecting this option will cause the mobile phone to initiate a standard voice call to our customer service.
• Customer service can be also dialed with virtual phone number +801801.
• The customer service number can be configured (see Configuration section).
• Volume adjusting with the dedicated phone hardware button (usually on the side of the phone).
• Mute/activate the microphone with dedicated "Mute" phone hardware button (usually with a circle shaped icon).

Network related improvements

• The stability of the CSD call was greatly improved and many new mobile operators are supported.
• Shortened call establishment (Connecting phase) to less than 15 seconds by using V.110 CSD dialing method (V.32 is still required on some network).
• Reduce latency and improve recovery time after phone signal outage with a new dynamic jitter buffer algorithm.
• Shorten recovery time after phone signal outage using new adaptive sending algorithm.
• The '+' international numbering plan selector prefix can be configured.

Security improvements

• Significant security improvements including better entropy gathering for higher quality key generation.

Defects fixed

• PrivateGSM can be configured to use different international numbering plan selector prefix for operators that does not support the default '+' sign.
• Some old and slow SIM cards did not allow secure calling with +801 prefix. This issue is fixed.
• PrivateGSM can now receive calls even during entropy collection.

PrivateGSM v9.03(r860)

New Features

• Reduced bandwidth requirements to average 4000bit/s using VAD (Voice Activity Detection).

Defects fixed

• Application crashed first time after startup when dialing a secure call with the +801 if it was not in the foreground yet.

Compatibility note

In order to provide VAD support, PrivateGSM v9.03 is incompatible with previous versions i.e. it can not create a secure call with PrivateGSM v9.02 or older. The older version should be upgraded in order to be able to connect a secure call with the new one. This situation is automatically detected on the device having the newer version and after the call has been hung up, the user is offered an option to send an upgrade invitation SMS to the other party having the outdated 9.02 version.

PrivateGSM v9.02(r731)

User interface improvements

• PrivateGSM application PrivatGSM folder in phone's application shell.
• Icon is shown when microphone is muted.
• Compatibility warnings for unsupported phones installation and usage time.

Security related improvements

• Elliptic curve Diffie-Hellman (ECDH) algorithm is used for public key exchange in place of standard Diffie-Hellman.

Network related improvements

• Network mode (GSM/UMTS) change directly from the application.
• Advanced CSD settings configuration UI.

Application management

• License code can be pushed via SMS.

Defects fixed

• E71 numeric dial bug.
• Interference with phone's address book.

PrivateGSM v9.00(r530)

New features

• Setting up a secure phone call through CSD channel (9.6kb/s).
• The full duplex audio flow is encrypted with ZRTP/S protocol that is an adaptation of the industry standard ZRTP secure audio streaming protocol.
• Dial a secure call from the application GUI as well as an integrated way into the phone's standard address book and dial interface.
• Answering incoming secure call.
• Invite other users via SMS.
• Set up a support account at Khamsa by sending an install notification to Khamsa's service number after first successful start.
• Support of different license states: full version, trial, receive only.
• Auto-start upon device boot in order to be able to respond to incoming secure calls. Settings page makes it possible to disable this feature.
• Watchdog process restart the application in case it was crashed.
• Dial a secure call using a secure prefix (+801) phone number.
• Remote party name is resolved from the phone's standard address book.
• Dialing from the application UI opens the phone's address book and the user can select any prefixed or non-prefixed number to initiate a secure call to.
• Inviting a friend from the application UI opens the phone's address book and the user can select any contact to send the invitation SMS to.
• Short installation wizard guides the user at first start-up time to accept the manufacturer's disclaimer, activate the product support with an SMS and to set up auto-start of the application.