Castel SIP vs SKYTEL UC
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Castel SIP
This application functions as a SIP intercom softphone, enabling users to make and receive audio and video calls from IP intercom stations on their mobile devices. It allows for communication and remote door opening, working through Wi-Fi and cellular data networks.
- Audio and video calls
- IP intercom station integration
- Remote door opening
- Address book with favorites
- Call history
- Remote commands during calls
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Castel SIP App is a SIP intercom softphone. The easy-to-use and intuitive application, allows you to make and receive audio and video calls from IP intercom stations (XELLIP, CAPIP...) on your iPhone or iPad. With Castel SIP App, you can communicate and open the door, anywhere. It works with the Castel Cloud SIP server through Wi-Fi and 3G/4G/5G. Main features: - Audio and video calls with advanced functionalities (Loudspeaker, transfer calls, hold...) - Address book with favorites - Call history - Remote commands during calls and DTMF - Support landscape and portrait mode for all smartphone and tablet designs (camera notch...) Note: Please, check your cellular operator's terms of agreement to make sure they allow SIP calls on their network before using Castel SIP App.
SKYTEL UC
This app is a SIP-based softphone for iPhone, enabling Wi-Fi or cellular calls and instant messaging. It integrates with your contacts for easy management and supports advanced call features like merging and transfers. Enjoy secure communication with encryption and high-definition audio and video.
- SIP-based softphone
- Wi-Fi or 4G/LTE calls
- Instant messaging
- Push notifications for calls/messages
- Contact list integration
- Call management (switch, merge, transfer)
- Video conferencing support
- Secure call signaling and encryption
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SKYTEL UC is a SIP-based softphone for iPhone that uses Wi-Fi or 4G/LTE connection to make and receive calls and Instant Messages. Interworking with SKYTEL PBX,SKYTEL UC support push notification, which allows it receive calls and messages even it was force terminated. By using iPhone's existing contact list, SKYTEL UC facilitates easy and effective communication management with an intuitive interface which accommodates multiple calls. Call functionality includes the ability to switch between two calls, merge and split calls and perform attended and unattended transfers. It also supports video conference which needs MCU support. SKYTEL UC incorporates advanced security settings which allows for secure call signaling and audio encryption. It supports up to 1080P video call with H.264 and VP8 codec, and supports HD audio call. Codecs offered includes: G.279, G.711a/u, Opus, AMR, AMR-WB, G.722.1, iLBC, GSM, SPEEX-WEB.
Screenshots
Verdict
The clearest difference is update cadence: SKYTEL UC at every 2 months against Castel SIP's every 4 months. SKYTEL UC also leads on iOS requirement (12.0 vs 15.5). On price, ads, in-app purchases and monetization model there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Castel SIP ships an update every 4 months, SKYTEL UC every 2 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.
| Parameter | Castel SIP | SKYTEL UC |
|---|---|---|
| Price | Free | Free |
| Rating | — | 5.0 (2 ratings) — better |
| Positive reviews | 60.0% of reviews | — |
| Number of ratings | — | 2 — better |
| Update frequency | Every 4 months | Every 2 months — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod — better | iPhone, iPod |
| Requires iOS | 15.5 | 12.0 — better |
| Further details — not scored | ||
| Size | 84 MB | 44 MB |
| Age rating | 4+ | 4+ |
| Developer | Castel | PortSIP Solutions, Inc. |
Customer experience
Castel SIP
SKYTEL UC
In-app purchases
Castel SIP
No in-app purchases
SKYTEL UC
No in-app purchases







