Comparison
Overview
Company snapshot and where each provider is based.
| Field | GatewayAPI | GMS |
|---|---|---|
| What it is | Danish SMS gateway and messaging platform by ONLINECITY.IO offering SMS, RCS and email APIs with pay-as-you-go pricing and EU data hosting. | Enterprise CPaaS and A2P messaging provider offering SMS, WhatsApp, Viber, RCS and email through a single API, plus messaging-hub and SMS-firewall services for mobile network operators. |
| Founded | 1999 | 2006 |
| Ownership | private | private |
| Employees | 11-50 | 500-1,000 |
| HQ city | Odense | Baar |
| HQ country | Denmark (EU) | Switzerland |
What's the differenceGatewayAPI edges ahead on the overall messaging.dev Score (54 vs 36). GatewayAPI is private and headquartered in Odense, Denmark (EU); GMS is private and based in Baar, Switzerland.
Channels
Which messaging channels each provider can send and receive on.
| Field | GatewayAPI | GMS |
|---|---|---|
| SMS | Yes | Yes |
| MMS | No | No |
| RCS | Yes | Yes |
| No | Yes | |
| Viber | No | Yes |
| Facebook Messenger | No | No |
| Telegram | No | No |
| Apple Messages for Business | No | No |
| Voice | No | No |
| Yes | Yes |
What's the differenceThey share 3 channels. GMS additionally offers WhatsApp, Viber.
Developer Experience
How quickly a developer can sign up and send a first message.
| Field | GatewayAPI | GMS |
|---|---|---|
| Self-service onboarding | Yes | No |
| Free developer credit | Test credits on request | No |
| Docs quality | med | med |
| Documentation | Open ↗ | Open ↗ |
| SDKs | — | iOS (Swift), Android (Kotlin) |
| Sandbox / test env | No | No |
| API types | REST, SMPP, Email-to-SMS | REST |
What's the differenceGatewayAPI offers Self-service onboarding, while GMS does not; on SDKs, GMS adds iOS (Swift), Android (Kotlin); on API types, GatewayAPI adds SMPP, Email-to-SMS.
Data & Compliance
Data residency options and enterprise compliance certifications.
| Field | GatewayAPI | GMS |
|---|---|---|
| EU data residency | Yes | Yes |
| US data residency | No | No |
| Choose region | Yes | No |
| GDPR | Yes | Yes |
| ISO 27001 | No | Yes |
| SOC 2 | No | No |
| HIPAA | No | No |
What's the differenceGatewayAPI offers Choose region, while GMS does not; GMS offers ISO 27001, while GatewayAPI does not.
Data Retention
How long message content and metadata are stored, and whether that is configurable.
| Field | GatewayAPI | GMS |
|---|---|---|
| Retention policy | Message content, sender and recipient are stored in the traffic log for 30 days, after which records are anonymized (message content and full sender deleted, last half of the recipient number removed). An optional "secret" message class skips storage of content, sender and recipient entirely. | Not publicly documented in detail. GMS's privacy notice states personal data is processed under EU GDPR (Regulation (EU) 2016/679) and held at its Switzerland headquarters (recognized by the European Commission as providing an adequate level of data protection); no specific retention periods for message content or metadata are published. GMS also holds ISO/IEC 27701 (privacy information management) certification. |
What's the differenceGatewayAPI: Message content, sender and recipient are stored in the traffic log for 30 days, after which records are anonymized (message content and full sender deleted, last half of the recipient number removed). An optional "secret" message class skips storage of content, sender and recipient entirely. GMS: Not publicly documented in detail. GMS's privacy notice states personal data is processed under EU GDPR (Regulation (EU) 2016/679) and held at its Switzerland headquarters (recognized by the European Commission as providing an adequate level of data protection); no specific retention periods for message content or metadata are published. GMS also holds ISO/IEC 27701 (privacy information management) certification.
Pricing & Credits
Pricing model and the cost of a first message.
| Field | GatewayAPI | GMS |
|---|---|---|
| Pricing model | Pay-as-you-go per-message pricing with prepaid credit; no monthly subscriptions or fees (except short-code countries), with negotiated discounts for high volumes. | Custom enterprise pricing negotiated with sales; no public self-service or per-message price list. |
| SMS starting price | From €0.0061 per SMS (standard class, cheapest destination on the public price list; e.g. €0.0401 to Denmark) | Not published |
| Free developer credit | Test credits on request | No |
What's the differenceGatewayAPI and GMS are closely matched on pricing & credits — no material differences in the tracked fields.
Reach & Reliability
Global coverage and delivery dependability.
| Field | GatewayAPI | GMS |
|---|---|---|
| Countries covered | 200 | 0 |
| Direct operator connections | Yes | Yes |
| Published uptime SLA | No published SLA (99.99%+ historical uptime claimed) | 99.99% network availability (claimed; no formal SLA published) |
What's the differenceGatewayAPI leads on Countries covered (200 vs 0 for GMS).
Company & Trust
Independent reviews and company profile.
| Field | GatewayAPI | GMS |
|---|---|---|
| G2 rating | 4.9 | 0.0 |
| G2 reviews | 7 | 0 |
| Ownership | private | private |
| Employees | 11-50 | 500-1,000 |
What's the differenceGatewayAPI leads on G2 rating (4.9 vs 0 for GMS); GatewayAPI leads on G2 reviews (7 vs 0 for GMS).
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