Comparison

Castel SIP vs SKYTEL UC

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

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.

Highlights
  • Audio and video calls
  • IP intercom station integration
  • Remote door opening
  • Address book with favorites
  • Call history
  • Remote commands during calls
Features
Read full description

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.

About

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.

Highlights
  • 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
Features
Read full description

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

Castel SIP4 screens
SKYTEL UC4 screens

Verdict

The call

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

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

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.

Scorecard2 real differences · 8 level
Castel SIP versus SKYTEL UC: the parameters behind the verdict, then further details
ParameterCastel SIPSKYTEL UC
PriceFreeFree
Rating—5.0 (2 ratings) — better
Positive reviews60.0% of reviews—
Number of ratings—2 — better
Update frequencyEvery 4 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.512.0 — better
Further details — not scored
Size84 MB44 MB
Age rating4+4+
DeveloperCastelPortSIP Solutions, Inc.

Customer experience

Castel SIP

Written reviews5 reviews
Positive60.0%
Neutral0.0%
Negative40.0%

SKYTEL UC

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Castel SIP

No in-app purchases

None

SKYTEL UC

No in-app purchases

Questions

Is Castel SIP free?
Castel SIP is free to download, with no in-app purchases.
Is SKYTEL UC free?
SKYTEL UC is free to download, with no in-app purchases.
Do Castel SIP or SKYTEL UC have ads?
Neither Castel SIP nor SKYTEL UC shows ads.
Which is updated more often, Castel SIP or SKYTEL UC?
Castel SIP ships an update every 4 months, and SKYTEL UC every 2 months. Most recently, Castel SIP was updated on November 1, 2026 and SKYTEL UC on November 3, 2026.

Other comparisons