Comparison

Overview

Company snapshot and where each provider is based.

FieldGMSRule
What it isEnterprise 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.Swedish marketing automation platform (Rule Communication Nordic AB) for email, SMS and RCS campaigns, with a REST API for transactional message sending.
Founded20062007
Ownershipprivateprivate
Employees500-1,00010-50
HQ cityBaarStockholm
HQ countrySwitzerlandSweden (EU)
What's the differenceGMS edges ahead on the overall messaging.dev Score (36 vs 28). GMS is private and headquartered in Baar, Switzerland; Rule is private and based in Stockholm, Sweden (EU).

Channels

Which messaging channels each provider can send and receive on.

FieldGMSRule
SMSYesYes
MMSNoNo
RCSYesYes
WhatsAppYesNo
ViberYesNo
Facebook MessengerNoNo
TelegramNoNo
Apple Messages for BusinessNoNo
VoiceNoNo
EmailYesYes
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.

FieldGMSRule
Self-service onboardingNoYes
Free developer creditNoNo
Docs qualitymedmed
DocumentationOpen ↗Open ↗
SDKsiOS (Swift), Android (Kotlin)Node.js, PHP
Sandbox / test envNoNo
API typesRESTREST
What's the differenceRule offers Self-service onboarding, while GMS does not; on SDKs, GMS adds iOS (Swift), Android (Kotlin); Rule adds Node.js, PHP.

Data & Compliance

Data residency options and enterprise compliance certifications.

FieldGMSRule
EU data residencyYesYes
US data residencyNoNo
Choose regionNoNo
GDPRYesYes
ISO 27001YesNo
SOC 2NoNo
HIPAANoNo
What's the differenceGMS offers ISO 27001, while Rule does not.

Data Retention

How long message content and metadata are stored, and whether that is configurable.

FieldGMSRule
Retention policyNot 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.Privacy policy states Rule only works with partners that process personal data within the EU/EEA (or that maintain an equivalent level of protection), keeps data only as long as a customer relationship exists or it remains relevant, and does not use marketing data older than 3 years. No specific retention period for message content or logs is publicly documented.
What's the differenceGMS: 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. Rule: Privacy policy states Rule only works with partners that process personal data within the EU/EEA (or that maintain an equivalent level of protection), keeps data only as long as a customer relationship exists or it remains relevant, and does not use marketing data older than 3 years. No specific retention period for message content or logs is publicly documented.

Pricing & Credits

Pricing model and the cost of a first message.

FieldGMSRule
Pricing modelCustom enterprise pricing negotiated with sales; no public self-service or per-message price list.Subscription tiers by contact-list size (free 250-contact plan without SMS, Professional from €595/month for 2,500 contacts, custom Enterprise) plus per-message SMS/RCS fees; a standalone SMS/RCS plan with unlimited contacts costs €100/month plus per-message rates.
SMS starting priceNot publishedFrom €0.04 per SMS (0.40 SEK per SMS in Sweden), on top of the monthly plan
Free developer creditNoNo
What's the differenceGMS and Rule are closely matched on pricing & credits — no material differences in the tracked fields.

Reach & Reliability

Global coverage and delivery dependability.

FieldGMSRule
Countries covered00
Direct operator connectionsYesNo
Published uptime SLA99.99% network availability (claimed; no formal SLA published)No published SLA
What's the differenceGMS offers Direct operator connections, while Rule does not.

Company & Trust

Independent reviews and company profile.

FieldGMSRule
G2 rating0.04.5
G2 reviews09
Ownershipprivateprivate
Employees500-1,00010-50
What's the differenceRule leads on G2 rating (4.5 vs 0 for GMS); Rule leads on G2 reviews (9 vs 0 for GMS).

Still deciding? Read the quickstart guides: