Comparison

SDKH Phone vs Second Phone Number²

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

Head to head
About

SDKH Phone

Features
Read full description

Heyday Phone allows you to make calls between extensions of the same company as well as adapting specific functionalities of a company such as transferring calls and placing a call on hold when necessary.

About

Second Phone Number²

Obtain real, functional phone numbers with unlimited calling and texting. Ideal for an additional line, it offers numbers across 300+ US area codes and in over 20 countries globally, ensuring privacy for your primary number.

Highlights
  • Acquire local numbers globally
  • Unlimited calling and texting
  • Integrate with existing contacts
  • Call forwarding
  • WiFi or data access
  • No contracts or hidden fees
Features
Read full description

Second Phone Number² Free Text & Calls Elevate Your Communication Globally. Say goodbye to the inconvenience of carrying extra devices or changing SIM cards. With Second Phone Number², experience the freedom of obtaining real, fully-functional phone numbers endowed with unlimited call and text capabilities. Ideal for those seeking an additional line, our service extends across more than 300 area codes within the US and now proudly offers local numbers in over 20 countries worldwide. Second Phone Number² is dedicated to ensuring your communications are kept private and distinct from your primary line. Whether for personal or business purposes, the numbers you acquire through our app operate independently, guaranteeing the privacy of your main number. This invaluable feature makes Second Phone Number² indispensable for secure online dating, confidential shopping, safe travel, and more, providing a dependable and private communication channel wherever you are in the world. Core Features: - Acquire local numbers from over 300 area codes across the US and in over 20 countries globally. - Unlimited calling and texting to local and mobile numbers, ensuring you stay connected without boundaries. - Integrate seamlessly with your current contacts for effortless communication. - Convenient call forwarding to your primary number. - Access Second Phone Number² on any connected device, be it over WiFi or data. Second Phone Number² is designed for ease and simplicity, requiring no contracts, hidden fees, or verification processes. Focused on privacy, it allows you to manage and discard numbers as needed securely. Whether you need a secondary number for international business dealings, online transactions, or maintaining anonymity across borders, Second Phone Number² is your premier choice for a secure, private, and comprehensive telecommunication solution. Information About Subscription You can cancel your subscription or free trial anytime by cancelling your subscription through your iTunes account settings, or it will automatically renew. This must be done 24 hours before the end of the free trial or any subscription period to avoid being charged. Subscription with a free trial period will automatically renew to a paid subscription. Please note: any unused portion of a free trial period (if offered) will be forfeited when you purchase a premium subscription during the free trial period. Subscription payments will be charged to your iTunes account at confirmation of your purchase and upon commencement of each renewal term. For more information, please see our Privacy Policy and Terms of Use. Privacy Policy: https://2ndsecond.xyz/privacy Terms of Use : https://2ndsecond.xyz/terms

Screenshots

SDKH Phone4 screens
Second Phone Number²4 screens

Verdict

The call

The clearest difference is in-app purchases: SDKH Phone at none against Second Phone Number²'s 10. Second Phone Number²'s advantage is update cadence (weekly vs every 22 months). On price, ads, device support and iOS requirement 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. Second Phone Number² sells 10 in-app purchases, starting at $5.99 per month. SDKH Phone asks for nothing beyond the download.

UpkeepUpdate frequency

SDKH Phone ships an update every 22 months, Second Phone Number² weekly. The most recent releases landed on November 7, 2026 and November 4, 2026 respectively.

Scorecard2 real differences · 8 level
SDKH Phone versus Second Phone Number²: the parameters behind the verdict, then further details
ParameterSDKH PhoneSecond Phone Number²
PriceFreeFree
Rating—4.4 (7 ratings) — better
Positive reviews—0.0% of reviews
Number of ratings—7 — better
Update frequencyEvery 22 monthsWeekly — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Free with in-app purchases
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better16.0
Further details — not scored
Size18 MB19 MB
Age rating4+4+
Developerheyday devAppios Bilisim

In-app purchases

None

SDKH Phone

No in-app purchases

10 purchases

Second Phone Number²

Subscriptions8
  • 1st Phone Number Monthly$5.991 Month
  • 2st Phone Number Monthly$5.991 Month
  • 2st Phone Number Monthly$9.991 Month
Show 5 more
  • 1st Phone Number Monthly$9.991 Month
  • 1st Phone Number Monthly$14.991 Month
  • 2st Phone Number Monthly$14.991 Month
  • 1st Phone Number Monthly$19.991 Month
  • 2st Phone Number Monthly$19.991 Month
One-time2
  • 100 Credits$2.99
  • 500 Credits$9.99

Questions

Is SDKH Phone free?
SDKH Phone is free to download, with no in-app purchases.
Is Second Phone Number² free?
Second Phone Number² is free to download, with in-app purchases available.
Do SDKH Phone or Second Phone Number² have ads?
Neither SDKH Phone nor Second Phone Number² shows ads.
Which is updated more often, SDKH Phone or Second Phone Number²?
SDKH Phone ships an update every 22 months, and Second Phone Number² weekly. Most recently, SDKH Phone was updated on November 7, 2026 and Second Phone Number² on November 4, 2026.

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