Software Alternatives & Startups

VirtualSMS.io VS https://open-gpt.app/

Compare VirtualSMS.io VS https://open-gpt.app/ and see what are their differences

VirtualSMS.io

Real SIM cards for OTP verification — 145+ countries, 2500+ services (WhatsApp, Telegram, Discord). From $0.05/code. API + MCP server for developers and AI agents.

Rating
0 reviews
Pricing
Freemium $0.05 (Per OTP code, pay-per-use, no contracts.)
https://open-gpt.app/

Create ChatGPT Application in seconds

Rating
0 reviews
Note: These products don't have any matching categories. If you think this is a mistake, please edit the details of one of the products and suggest appropriate categories.

Base details

Website, pricing, platforms and company facts side by side.

VirtualSMS.io
https://open-gpt.app/
Website virtualsms.io open-gpt.app
Pricing
Freemium $0.05 (Per OTP code, pay-per-use, no contracts.) Official pricing
—
Platforms
REST API PHP
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Company 10 - 19 employees · 2025 —
Listed in —

About VirtualSMS.io and https://open-gpt.app/

In their own words, as submitted to SaaSHub.

VirtualSMS.io
https://open-gpt.app/

VirtualSMS is a developer-first SMS verification API that uses real SIM-backed phone numbers, not VoIP. Receive OTP codes for any service that sends SMS — built for signup testing, account verification, 2FA flows, and autonomous AI agent workflows. Why VirtualSMS Real SIM numbers work where VoIP...

Read more about VirtualSMS.io

No description of https://open-gpt.app/ yet.

Features and specs

What each product offers, as listed by its team.

VirtualSMS.io 13 features
https://open-gpt.app/ 5 features
  • Countries Supported
    145+
  • Services Supported
    2,500+ (WhatsApp, Telegram, Discord, Gmail, social apps)
  • Number Type
    Real SIM cards (not VoIP)
  • MCP Server
    Yes (Model Context Protocol)
  • x402 Stablecoin Payments
    Yes (Base / Polygon / Arbitrum / Optimism)
  • Webhooks
    Yes (async event notifications)
  • OpenAPI Spec
    Yes (v1.1.0, machine-readable)
  • Auto-Refund
    Yes (on failed delivery)
  • Authentication
    API Key (X-API-Key header)
  • Public Price Endpoint
    Yes (no auth required)
  • CORS Enabled
    Yes (browser + AI agents)
  • Legacy Compatibility
    sms-activate-style at /stubs/handler_api.php
  • Response Format
    JSON
  • Accessible AI Chat Interface
    Provides a user-friendly web-based interface for interacting with GPT-based AI models without needing to set up API access or coding knowledge.
  • No Installation Required
    Being a web application, it can be used directly from a browser without downloading or installing any software.
  • Potentially Free or Low-Cost Access
    Many GPT wrapper sites like this offer free tiers or lower-cost access compared to official API pricing, making AI chat more accessible to casual users.
  • Quick Setup
    Users can typically start chatting almost immediately after visiting the site, with minimal account creation or configuration steps.
  • Cross-Platform Compatibility
    Since it runs in a browser, it can be accessed from various devices including desktops, tablets, and smartphones without platform-specific versions.

Possible disadvantages

  • Uncertain Reliability
    Third-party GPT wrapper websites often depend on underlying API access that can be unstable, rate-limited, or discontinued without notice, affecting consistent availability.
  • Data Privacy Concerns
    Using an unofficial third-party service to process conversations raises questions about how user data and conversation history are stored, used, or shared.
  • Limited Transparency
    It may be unclear which underlying AI model version is being used, how up-to-date it is, or what modifications have been made to the base model's behavior.
  • Potential Hidden Costs or Ads
    Free-to-use AI wrapper sites often monetize through ads, premium upsells, or data collection, which may not be clearly disclosed to users upfront.
  • Lack of Official Support
    Unlike official AI platforms, unofficial wrapper sites may lack dedicated customer support, regular updates, or accountability if issues arise.

Analysis

An editorial look at what each product does well and who it suits.

VirtualSMS.io
https://open-gpt.app/

Overall verdict

  • VirtualSMS.io appears to be a functional virtual phone number and SMS verification service that offers a convenient way to receive text messages online, though as with many services in this category, users should verify its current reliability and reputation before committing.

Why this product is good

  • Provides temporary or virtual phone numbers for receiving SMS without using your personal number
  • Useful for protecting privacy when signing up for online services and apps
  • Typically supports one-time password (OTP) and verification code reception
  • Often offers numbers from multiple countries for regional flexibility
  • Can be a cost-effective alternative to buying physical SIM cards for verification

Recommended for

  • Users who want to protect their personal phone number when registering for online accounts
  • Businesses needing bulk SMS verification for testing or account creation
  • Developers testing SMS-based features and integrations
  • People who need a temporary number for one-time verifications
  • Privacy-conscious individuals avoiding spam on their primary number

Overall verdict

  • I don't have verified, up-to-date information about open-gpt.app, and I'm unable to browse the internet to check its current status, reputation, or legitimacy. I cannot confidently vouch for or against this specific product/service.

Why this product is good

  • I lack real-time access to verify this website's current content, reputation, or user reviews
  • Domain names and their associated services can change ownership and purpose over time
  • Without verification, I cannot confirm if this is a legitimate service, its features, or its safety
  • There are many similarly-named AI tools of varying quality and trustworthiness, making specific verification important

Recommended for

  • Before using this site, research current user reviews on trusted platforms
  • Check the site's SSL certificate, privacy policy, and terms of service
  • Look for verified information about the company or developers behind it
  • Consider well-established alternatives like ChatGPT (OpenAI), Claude (Anthropic), or Gemini (Google) if you need reliable AI assistance
  • Exercise caution with any site requesting payment or personal information without clear verification of legitimacy

Category popularity

How often each product is chosen within a category, 0–100% relative to the other.

Score bands 0–20 21–40 41–50 51–60 61–100
VirtualSMS.io
https://open-gpt.app/
100% 100%
0% 0%
100% 100%
0% 0%
100% 100%
SMS
0% 0%
100% 100%
0% 0%

Questions & Answers

As answered by people managing VirtualSMS.io and https://open-gpt.app/.

What makes your product unique?

VirtualSMS.io's answer

VirtualSMS uses real SIM-backed phone numbers, not VoIP — so it works with services that reject VoIP (WhatsApp Business, Telegram bot at scale, banking apps, dating platforms). It's also the only SMS verification API that ships with an MCP server for AI agents and x402 stablecoin payment support — making it the first SMS API designed for both developers and autonomous AI agents.

Why should a person choose your product over its competitors?

VirtualSMS.io's answer

Three reasons:

  1. Real SIM numbers work where VoIP fails. Most competitors (5SIM, SMS-Activate, SMSPVA) lean heavily on VoIP. That gets blocked by services that matter — WhatsApp Business, banking apps, dating platforms. Our numbers don't.

  2. Built-in MCP server for AI agents. Claude, Cursor, ChatGPT, and any MCP-compatible AI agent can handle phone verification autonomously through our MCP server. No other SMS API in this category ships with this.

  3. Pay-per-use, no contracts, no minimum deposit. From $0.05/code. Free API key. Public price endpoint lets you check pricing before signing up. Auto-refund on failed deliveries. x402 stablecoin payments for international developers who want to skip KYC.

How would you describe the primary audience of your product?

VirtualSMS.io's answer

Developers building OTP-dependent workflows: signup testing, QA automation, account verification at scale, and onboarding flows.

Growing segment: AI agent builders using MCP-compatible tools (Claude Code, Cursor, ChatGPT) that need autonomous phone verification capability.

Also: teams migrating from legacy SMS verification providers that no longer meet their needs — either because their suppliers shut down or because their numbers are now blocked as VoIP.

What's the story behind your product?

VirtualSMS.io's answer

VirtualSMS launched because every SMS verification API on the market was either VoIP-only — rejected by WhatsApp, banking apps, and most major services — or built around legacy plain-text protocols that modern AI agents couldn't use natively.

We started with a modern REST API and real-SIM-backed numbers. We added an MCP server from day one, making us the first SMS verification service designed for both developers and autonomous AI agents. x402 stablecoin payment support followed — removing KYC friction for international developers who'd been priced out of legacy providers.

Which are the primary technologies used for building your product?

VirtualSMS.io's answer

REST API over HTTPS with OpenAPI 3.1 specification

TypeScript MCP server (Model Context Protocol)

Mintlify-hosted developer documentation

x402 stablecoin payment protocol on Base / Polygon / Arbitrum / Optimism

WebSocket for real-time SMS delivery notifications

Webhook event notifications for async integration

sms-activate-style legacy compatibility endpoint (/stubs/handler_api.php) for drop-in migration

Who are some of the biggest customers of your product?

VirtualSMS.io's answer

-AI agent platforms integrating our MCP server for autonomous phone verification

-E-commerce QA automation teams testing signup and checkout flows

-Crypto-native developer projects using x402 stablecoin payments

-Developers migrating from sms-activate-style legacy providers

User comments

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