SmartLine Second Phone Number vs String
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
SmartLine Second Phone Number
Get a dedicated second phone number for your business to maintain privacy and professionalism. This app ensures calls are business-related, offers a spam filter, custom voicemail, and voicemail-to-text transcription. Manage your business communications efficiently with organized history and timely notifications.
- Dedicated business phone number
- Professional call quality (not VoIP)
- Spam call filtering
- Customizable voicemail greetings
- Voicemail to text transcription
- Set business hours for calls
- Organized call and text history
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SmartLine is a second phone number for your business. When you receive a call through SmartLine, you know it’s for business so you can answer professionally. When you call or text through SmartLine, customers see your new business phone number so your personal number stays private. - Professional Quality. Calls use your cellular connection – NOT VOIP – to give you the call clarity and reliability you need to sound professional. - Spam Call Filter. Answer calls with confidence because spam calls are sent directly to voicemail. - Custom Voicemail. Record a custom voicemail greeting to prompt callers to leave a message. - Voicemail to Text. Get your business voicemail automatically transcribed to text to save you time. - Set Business Hours. Choose when you’re available for business calls and send callers to voicemail after hours. - Stay Organized. See your conversation history of calls, texts, pictures, and voicemail, organized by contact. - Stay Notified. Be notified and follow up quickly whenever you have missed calls, voicemail messages, or texts. -- Terms -- An existing SmartLine subscription is required to use this app. Currently available in the US only. SmartLine will automatically renew via iTunes, unless you cancel 24 hours before the the end of the current billing period. Easily manage and cancel your SmartLine 2nd phone number at any time through your iTunes subscription settings. If you didn't purchase SmartLine through iTunes, you can manage your subscription through the GoDaddy website. Terms of use: https://www.godaddy.com/legal-agreements.aspx Privacy policy: https://www.godaddy.com/Agreements/Privacy.aspx
String
Enhance customer engagement with a business SMS and voice platform. Organize your inbox, automate responses, and manage contacts efficiently. Send personalized messages to individuals or groups, and access your workflow from any device.
- Use existing or new phone numbers
- Organize inbox with sales funnel view
- Automated responses and auto-replies
- Contact management and CRM integrations
- 1-1, group, and mass messaging
- Templates and voicemail transcription
- Browser and mobile app access
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Boost your brand engagement with String’s intuitive business SMS marketing, text and voice. ANY PHONE NUMBER, EVEN LANDLINES Use your existing mobile or landline number with String. Select a new local number or upgrade to a vanity or toll free number of your choice. ORGANIZE YOUR INBOX Transform your inbox into a sales funnel or kanban board with various viewing, filtering and tagging options — Stay on top of your conversations and never miss a message again. POWERFUL MESSAGE MANAGEMENT Mark Unread and Archive — You love it for your emails, you’ll love it for your texts. STAY RESPONSIVE, 24/7 Amplify your interaction with automations and Auto-Replies — Respond to texts and missed calls on time, every time. TAP INTO ENDLESS POSSIBILITIES Contact Management & Integrations — Save important contact notes directly from the message thread. Capture contacts, import from your phone or computer,, automate workflows, integrate with tools you love (like your CRM, etc). REACH THE MASSES, OR JUST ONE Conversational, Groups or Mass Messaging — Respond directly with 1-1 messaging, message with a group,r or send personalized Mass Messages to multiple people at once, individually. BUILD A LOYAL CUSTOMER BASE Send promos, reminders and confirmations and never miss a lead, client or customer with Elite features like triggered Keyword Responses, and Auto-Replies. SAVE TIME Templates — No more copy-pasting the same message over and over. No time to listen to voicemail? View voicemail transcriptions in your inbox with visual voicemail. USE IT ANYWHERE Browser & Mobile Apps — Increase your workflow efficiency with access to String from your computer and mobile device. CALL FORWARDING & VOICE Separate your personal and professional calls with call forwarding and flexible voice settings. GOT QUESTIONS? Email our stellar support at support@joinstring.com. Find helpful articles, join our customer community and create tickets in our Help Center: https://help.joinstring.com/hc/en-us Terms of Service: https://www.joinstring.com/terms Privacy Policy: https://www.joinstring.com/privacy
Screenshots
Verdict
The clearest difference is review sentiment: String at 69% against SmartLine Second Phone Number's 15%. String also leads on monetization model (free with in-app purchases vs subscription). SmartLine Second Phone Number's advantage is rating (4.7 vs 3.5) and ratings volume (44K vs 62). On price, update cadence, ads and in-app purchases 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.
SmartLine Second Phone Number holds the better App Store score, 4.7 against 3.5. That said, the two scores are not equally well evidenced: SmartLine Second Phone Number has 44K ratings behind it against 62, so its average is the more settled of the two. Written reviews complicate that: 15% of SmartLine Second Phone Number's written reviews are positive against 69% of String's, so the app with the better star average is not the one people write more warmly about.
Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on November 10, 2026 and November 2, 2026 respectively.
| Parameter | SmartLine Second Phone Number | String |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (44K ratings) — better | 3.5 (62 ratings) |
| Positive reviews | 15.5% of reviews | 68.6% of reviews — better |
| Number of ratings | 44K — better | 62 |
| Update frequency | Every 2 months | Every 2 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Subscription | Free with in-app purchases — better |
| Devices | iPhone, iPod | iPhone, iPad, iPod — better |
| Requires iOS | 12.1 — better | 15.0 |
| Further details — not scored | ||
| Size | 75 MB | 68 MB |
| Age rating | 4+ | 4+ |
| Developer | GoDaddy.com, LLC | NumberBarn, LLC |
Customer experience
SmartLine Second Phone Number
String
User reviews
SmartLine Second Phone Number
From 44K App Store ratingsWhat we love
- 🚀 Convenient business line
- 📝 Stores call/text history
- ⏱️ Ability to set business hours
Room to improve
- 🐛 Unreliable text messaging
- 📞 Missed/dropped calls
- 🔔 Delayed/missing notifications
- 🤖 Poor customer support
String
From 62 App Store ratingsWhat we love
- 👍 Organizes texts like email
- 🚀 Efficient for business communication
- 💡 Automates common questions
- 👍 Easy to use interface
- 👍 Great for small businesses
Room to improve
- 🐛 Mobile app is buggy
- 🐛 Website loads to white screen
- 🐛 App loads messages out of order
- 🐛 Threads don't load
- 🐛 Incorrect contact loading
Bugs and requests
SmartLine Second Phone Number
Reported bugs
3 issues- Disappearing call/text history
- Incorrect number display on outgoing calls
- Failure to sync across devices
Requested features
4 requests- Ability to send multiple photos/files
- Improved caller ID display
- Option to have multiple voicemail greetings
- Compatibility with VPNs and older devices
String
Reported bugs
22 issues- Calls drop within seconds
- Line cuts out completely
- Website loads to a white screen
- App loads message threads out of order
- Tapping into a thread does not load any part of the conversation
Show 17 moreShow fewer
- Sending a message in the thread works, but the thread doesn’t load
- Tapping a thread loads an entirely different number/contact at the top
- Push notification badges don’t clear
- Text threads are slow to update and sometimes show off screen
- No where to sign up on the app
- Lost account after uninstall/reinstall
- No one to talk to for support
- iTunes account debited without loading sign-in page
- Stuck on unpaid account, cannot log out
- Missed calls do not show up on the main log panel
- Voicemails will not play in app
- No iPad App
- Web app directs back to mobile app
- No attention to detail in integrations
- Phone number picker is super limited
- No filtering by numbers
- Requires payment to see the app
Requested features
18 requests- Improve mobile app stability
- Fix website loading issues
- Ensure message threads load correctly
- Improve contact loading accuracy
- Fix push notification badge issues
Show 13 moreShow fewer
- Improve text thread update speed
- Enhance call stability
- Improve customer support responsiveness
- Provide in-app sign-up
- Allow account recovery
- Offer refunds
- Implement missed call notifications
- Ensure missed calls appear in logs
- Enable voicemail playback in app
- Develop an iPad app
- Improve sign-up process
- Add more phone number filtering options
- Integrate with CRM software like HubSpot
In-app purchases
SmartLine Second Phone Number
No in-app purchases
String
No in-app purchases
Questions
Is SmartLine Second Phone Number free?
Is String free?
Which has better reviews, SmartLine Second Phone Number or String?
Do SmartLine Second Phone Number or String have ads?
Which is updated more often, SmartLine Second Phone Number or String?
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