From Finarea SA:
MobileVOIP is a free iPhone cheap calls app which lets you make (free) national or international mobile voip calls directly from your iPhone. You can save on your Mobile Phone costs by simply installing the MobileVOIP app and start making cheap calls. Make sure you have enabled MobileVOIP in the privacy settings (microphone) on your iOS device. Select any contact from your contact list, which is accessible in the app, and start your call using MobileVOIP anywhere, anytime. MobileVOIP operates over multiple internet connection options (3G, WiFi, GPRS, Edge, UMTS) directly from one integrated contact list. Install MobileVOIP now and start making free 3g calls and WiFi calls today; no need for expensive calling plans anymore. Even when abroad, you can save money on your international phonecalls to friends and family back home: simply find a public WiFi access point and save on monthly calling charges. Know Issues: After updating to iOS7, some users may experience issues with their microphone. Solve this issue by going to: Settings > Privacy > Microphone, turn on the MobileVOIP switch there. FEATURES. Make SIP phone calls on your iPhone. Make FREE calls to a selection of destinations using your iPhone. Make cheap calls to any international destination. Send Cheap Text Messages (SMS) worldwide. Save on calling charges using Wifi, GPRS, EDGE or UMTS. Select regular contacts from contact list to make a call. Works all around the globe: anywhere, anytime. Bypass voip blockades with MobileVOIP. Low Bandwidth; save on roaming. Over 50 VoIP providers supported. Make sure you have an account already, before using the MobileVOIP app. Supported VoIP Brands: 12Voip, Actionvoip, BudgetVoipCall, CallPirates, CallingCredit, CheapBuzzer, CheapVoipCall, Cheapvoip, CosmoVoip, DialCheap, DialNow, DiscountCalling, Easyvoip, FreeCall, Freevoipdeal, Frynga, GlobalFreecall, HotVoip, InternetCalls, Intervoip, Jumblo, JustVoip, LowRateVoip, MegaVoip, NetAppel, NoNoh, PennyConnect, PoivY, Powervoip, RebVoice, Rynga, SMSDiscount, SipDiscount, SmartVoip, SmsListo, SparVoip, StuntCalls, Telbo, VoipBlazer, VoipBuster, VoipCaptain, VoipCheap, VoipCheap UK, VoipChief, VoipDiscount, VoipGain, VoipJumper, VoipMove, VoipRaider, VoipSmash, VoipStunt, VoipWise, VoipZoom, Voipblast, VoipYO, WebcallDirect.