What Sideline does

Sideline is a subscription-based mobile application that provides consumers and small businesses with a second phone number on their existing iOS or Android device, enabling separation of personal and professional communications without additional hardware. The product is owned and operated by Pinger, Inc., a private San Jose, California-based corporation, and is one of several apps in Pinger's portfolio alongside the free, ad-supported TextFree and the small-business platform Index. The product is distributed exclusively through the Apple App Store and Google Play with no public API or third-party integrations, and is available in the US and Canada (the latter via Pinger's subsidiary Dinopilot).

Sideline's core technical differentiator is a patented carrier-level call routing mechanism that connects calls via the user's cellular network rather than VoIP, yielding superior call quality and reliability versus competitors such as Burner, Line2, and Google Voice. Built-in features include unlimited calling and SMS/MMS, voicemail-to-text transcription, auto-reply for missed calls/texts, number porting, spam detection and unknown-caller labeling, group messaging, and a companion web-based messaging portal at messages.sideline.com. The product targets two primary segments: privacy-conscious individuals who want to shield their personal number when transacting with strangers or businesses, and small business owners and entrepreneurs who need a professional line without a second physical device. A prior Enterprise plan (with auto-attendants and multi-user support) was discontinued in June 2025, narrowing the focus back to individual and micro/SMB customers.

The business model is a recurring subscription (monthly or annual) for the second-number service, supplemented by minor promotional placements within the app. The go-to-market motion is product-led and direct-to-consumer: users self-onboard via app stores with no sales interaction. No external venture or private equity funding is disclosed, and the company operates under its parent Pinger's corporate umbrella rather than as an independent fundraising entity. Founders Joe Sipher (Co-founder & CPO) and Greg Woock (Co-founder & CEO) are named in public materials, though no broader management team or headcount data is reported.

Name

Sideline

Legal name

Pinger, Inc.

Website

https://sideline.com

Company type

Private

Founded year

2015

Operating status

Operating

Short description

Sideline is a subscription-based iOS and Android app providing a second phone number with patented carrier-level call quality, serving privacy-conscious individuals and small business owners in the US and Canada.

Ownership category

akta.pro rank

Product category

Second Phone Number Service

NAICS

Wired and Wireless Telecommunications (except Satellite) (5171), All Other Telecommunications (517810)

SIC

Radiotelephone Communications (4812), Communications Services, Nec (4899)

akta.pro primary industry

Telephony Hardware, Endpoints & Room Systems (HDAIAHAJ)

akta.pro secondary industry

SMS/RCS Messaging Platforms (BPAMACAF)

Keywords

• Second phone number
• Mobile communication app
• Business texting software
• Caller ID services
• Voicemail transcription

Headquarters

HQ city

San Jose

HQ country

United States

HQ region

North America

Markets served

GTM type

B2C

Offering type

Software

Cost components

Technology or R&D, Marketing or Sales, Personnel, Infrastructure, Operations

Revenue model

1. Subscription-based second phone number service: Sideline requires a paid subscription for its second phone number service. The app provides phone numbers, voicemail, voicemail-to-text, inbound call routing, multi-device call notification, and text messaging. Revenue is generated through recurring monthly or annual subscriptions rather than advertising.
2. Promotional placements within Sideline app: Sideline may include promotional placements within the app, though it is primarily a subscription service rather than ad-supported like Pinger's other apps (TextFree)

Go-to-market motion2 records

Distribution channels3 records

Marketing channels5 records

Core offering

Sideline is a subscription-based mobile app that provides users with a second phone number on their existing iOS or Android device, enabling unlimited calling, texting, and voicemail without requiring additional hardware or SIM cards. The service uses patented carrier-level network connectivity rather than VoIP to deliver superior call quality, and includes features such as voicemail-to-text transcription, spam detection, number porting, auto-reply, and a desktop web messaging portal.

Product overview

Sideline is a single-product subscription-based second phone number service for iOS and Android. The core Sideline app provides a reliable 2nd number with unlimited calling, texting, and voicemail using patented carrier-level network technology. Three feature modules—2nd Number (phone number management with porting and caller ID), Work Texting (business communication with branded messages and group messaging), and Auto-Reply (automated responses to missed calls/texts)—are built into the platform. An optional web portal called Sideline Web extends functionality to desktop browsers. The product is distinct from sister apps TextFree, TextFree Voice (free, ad-supported), and Index (a separate small business platform with appointment booking and payment features) which are also operated by parent company Pinger.

Differentiator

Problem solved

Functional benefit

Products and services

• Sideline Mobile App A subscription-based second phone number app for iOS and Android that provides a reliable 2nd number with unlimited calling, texting, and voicemail, using carrier-level network connectivity for superior call quality. Targeted at privacy-conscious individuals and small business owners who want to separate personal and professional communications without a second device.
• Sideline Web Messaging A web-based texting portal that allows Sideline subscribers to manage their texts and calls from a desktop browser, extending the second phone number experience to larger screens. Targeted at current Sideline subscribers who want desktop messaging convenience.

Quantifiable outcome

• 11+ million downloads and 30,000+ 5-star reviews demonstrate strong user adoption and satisfaction
• +1 more outcomes

Named customers6 records

Segments3 records

Ideal customer profiles2 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Partnerships

One partnership is on record.

• Pinger, Inc.coreOthersPinger is the parent company and developer of Sideline. Pinger offers five software applications for iOS and Android including Pinger, TextFree, TextFree Voice, Sideline, and Index. Sideline is Pinger's subscription-based second phone number app targeting individual consumers.

Scale indicators4 records

Recent moves6 records

Expansion highlights4 records

Broad incumbents

• RingCentral: Established incumbent in business cloud communications with team phone numbers, call routing, and IVR. Relevant as the higher-end competitor now positioned to absorb SMB/team customers that Sideline is exiting.
• Google Voice: Free, broadly available second-number service from a major platform incumbent. Often the default free alternative cited in Sideline user testimonials as the competitor Sideline is chosen over, exerting significant pricing pressure.

Emerging players

• Quo (formerly OpenPhone rebrand of business tier): SMB-focused second-number / business phone service referenced in Sideline's competitive set at ~$15/user/month. Comparable as a paid, professional-grade alternative Sideline users are migrating to.
• OpenPhone: Emerging player in the modern business phone number space focused on small teams and SMBs. Comparable as a second-number subscription service, with stronger team/collaboration features that may pull SMB users from Sideline after its Enterprise exit.

Direct peers

• 2ndLine: Direct competitor providing a second phone number with calling/texting on Android and iOS, targeting similar consumer privacy and SMB use cases at low subscription price points.
• Hushed: Direct competitor in the second phone number / temporary number category, with similar feature set (voicemail, SMS/MMS, auto-reply) targeting both privacy users and small businesses on iOS and Android.
• Burner: Direct competitor offering disposable second phone numbers via mobile app with subscription pricing. Most frequently cited head-to-head rival on Sideline's own comparison pages and serves the same privacy-conscious consumer and SMB segments.
• GoDaddy SmartLine: Direct competitor bundled with GoDaddy's small business offerings, providing a second business number on mobile. Targets the same SMB/SOHO segment Sideline serves.
• Line2: Direct competitor offering a second phone line on mobile and desktop with business features; named alongside Sideline in customer comparisons for SMB and professional users.

Others

• TextFree (Pinger sister app): Sibling app under parent Pinger, Inc. providing free texting/phone numbers ad-supported. Not a direct competitor but adjacent in product and customer, representing the parent company's broader communications-app portfolio.

Market position

Strengths4 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights6 records

Customer concentration

• Xx.com/SidelineHQ
• YouTubeyoutube.com/c/Sidelinenumber
• Facebookfacebook.com/sidelineHQ
• LinkedInlinkedin.com/showcase/sideline-number
• Instagraminstagram.com/sidelinehq

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Subsidiaries1 record

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Sideline