Features & Capabilities

1SIM VoIP lets OneSimCard customers place and receive international calls over VoIP on iPhone and iPad, helping you save on roaming fees. You can choose whether calls go over the OneSimCard international SIM card or via the VoIP network, and incoming calls to your PEN can come through VoIP if registered. The app does not require a physical OneSimCard SIM in the phone, but you must have a OneSimCard account and a VOIP and SMS-enabled PEN, and you need a solid Internet connection (Wi‑Fi, 3G/4G/LTE).

Version 2 adds SMS texting to US and Canada at reduced rates and lets you send/receive texts over Wi‑Fi or mobile data. Initial setup is in the My SIM Cards section of your OneSimCard online account; you create a VoIP account and receive a settings link for iPhone or iPad. Note that call quality depends on your Internet connection and may differ from roaming network quality.

User Growth & Download Statistics

By:
Belmont Telecom, Inc.
Rating:
4.00
(2)
Version:
3.1.2 Last updated: 2026-05-14
Version code:
885628659
Creation date:
2012-03-28
Compatible devices:
Size:
85.23MB
URLs:
Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-06-09
Compare stats and ranking:

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
Belmont Telecom, Inc.
Apple Apps Store
https://apps.apple.com/in/app/1sim-voip/id510371587

User Reviews

User reviews show a mixed experience. Some users note updates have improved texting and calling, and the app offers very cheap international calling over Wi‑Fi (even without a SIM in some cases). However, many reports highlight serious reliability problems: crashes, dropped or failed calls, missed messages, and poor contact integration. The app also seems to depend on Wi‑Fi and performs poorly on cellular networks, with inconsistent support and occasional security concerns raised by users.
Pros
  • Recent updates have improved texting and calling reliability.
  • Very low-cost international calling over Wi-Fi, with some users able to use it without a physical SIM (OneSimCard case).
  • Wi-Fi based calling/texting can work when cellular service is unavailable.
Cons
  • Frequent crashes and failures to launch on various iPhone/iPad models and iOS versions.
  • Unreliable call quality and connectivity, including dropped calls, missed rings, and DTMF/prompt recognition issues.
  • Inconsistent SMS delivery; messages sometimes fail to send or be received.
  • Poor UI/UX and contact integration, with mislinked contacts and incorrect names.
  • Wi‑Fi only operation; poor performance over cellular networks (LTE/3G) and limited usability without Wi-Fi.
Recent reviews
I’ve had several friends tell me they tried calling me but, after a couple of rings, they lost the connection. Meanwhile, I heard no ring and did not get a missed call notice. Text messages also don’t always go through in either direction.
by La*****, 2025-07-15

This app is a complete nightmare to use.The user interface is very complicated, when I allowed to contacts and call a number it called another number not related to the first one.The API requests and responses of this app show plane-text passwords and plane-text user IDs. The communication is unencrypted… Furthermore, I didn’t use the app for one week and 1Sim blocked my account. Now I have to pay more to use my account which has funds. Worst experience I ever at. Never using it again.
by jo*****, 2025-02-07

Have been using it for long time
by Bi*****, 2024-10-14
View all user reviews ›

Best 1SIM VoIP Alternatives

Here are some Apple apps that are similar to 1SIM VoIP: