Overview

Duo Mobile is a mobile authentication app for adding a second factor to company and personal sign-ins. It is best for organizations securing a varied mix of applications and infrastructure. Its breadth of integration and policy controls is compelling for managed environments, but may be more than an individual needs from an authenticator.

Key features

Duo Push turns a login challenge into a one-tap approval or denial, while time-based passcodes offer a code-entry alternative. The iOS and Android apps also support third-party TOTP accounts, which lets users keep other authenticator codes alongside Duo-protected accounts. Biometrics, passcodes, and push give organizations multiple supported authentication controls rather than forcing every user into one sign-in path.

Duo Restore backs up and restores Duo-protected accounts when users switch Android or iOS devices, addressing a common continuity problem. Security Checkup sends a security score for a user's mobile device through Duo Mobile notifications. One operational trade-off is that users who need enrollment, activation, reactivation, or troubleshooting help must contact their organization's Duo administrator.

Administrators can integrate Duo with legacy infrastructure, major platforms, custom apps, VPNs, SaaS tools, and offline devices. Connection options include RADIUS, SAML/OIDC, Duo Authentication Proxy, and direct API integrations. Adaptive authentication can base access policies on role, location, application, network, and device health, making the product a stronger fit for organizations that need access rules to reflect context rather than just a successful second factor. The Duo Ecosystem marketplace lists 701 applications.

Duo's security design uses asymmetric cryptography, keeps private keys on users' devices in a tamper-proof secure element, and does not store passwords. Duo says it supports or aligns with PCI-DSS 4.0, NIST 800-63 and 800-171, DEA EPCS, GDPR, FFIEC, HIPAA, and PIPEDA requirements. The app works on Apple iOS and Google Android phones and tablets, and supports many smart watches.

Pricing

Duo offers a free plan and a 30-day trial. Duo Free costs 0.00 USD per free, billed monthly, and is capped at 10 users. That makes it a practical starting point for a small team, but the seat ceiling is a firm constraint for larger deployments.

Duo Essentials costs 3.00 USD per month and includes Duo Directory, phishing-resistant MFA, passwordless authentication, SSO, Trusted Endpoints, and unlimited applications. It is the entry paid tier for organizations that need those capabilities beyond the free-plan cap. Duo Advantage costs 6.00 USD per month and adds Cisco Identity Intelligence, Duo Passport, session theft protection, Active Directory Defense, and risk-based authentication; it better suits teams seeking additional identity and risk controls. Duo Premier costs 9.00 USD per month and adds Zero Trust access, VPN-less remote access, and a complete device trust check with endpoint protection, making it the tier for organizations that need those access and device protections. The listed plan terms do not establish a billing interval or seat allowance for the paid tiers, so buyers should confirm those before budgeting.

Platforms

Duo Mobile is available for iOS and Android, including phones and tablets, with support for many smart watches. Duo's integration options reach beyond those mobile platforms into VPNs, SaaS tools, offline devices, legacy infrastructure, and custom applications.

Who it's for

Duo Mobile makes most sense for organizations that need managed authentication across varied systems, with administrator controls and context-aware policies. The SSO, SCIM, device-posture, audit-log, credential-theft detection, directory-attack detection, and automated-response capabilities support a broader identity-security role; passwordless options include platform authenticators, passkeys, FIDO2 security keys, and Duo Push. A person seeking only standalone personal TOTP codes may find the organizational emphasis unnecessary, and teams above 10 users cannot stay on Duo Free.

Pros and cons

Broad integration reach: RADIUS, SAML/OIDC, proxy, and API options help connect authentication to varied infrastructure, including legacy and offline systems.
Several login paths: Push, passcodes, third-party TOTP, biometrics, and passwordless methods give organizations alternatives to a single approval flow.
Device transition support: Duo Restore backs up and restores Duo-protected accounts across iOS and Android device changes.
Small free-plan ceiling: Duo Free is limited to 10 users, so growing teams must move to a paid plan.
Administrator-dependent user support: End users needing account setup or troubleshooting help are directed to their organization, not an independent support path.

Alternatives

For a broad comparison of authentication tools, browse Multi-Factor Authentication Software; readers focused specifically on standalone code generators can compare Authenticator apps. If phishing-resistant, passwordless access is the priority, consider Passwordless Authentication Software or Passkey Authentication Software alongside Duo's supported passwordless options. Organizations evaluating threat detection can review Identity Threat Detection and Response Software, while VPN-focused buyers can compare Business VPN Software.

Bitdefender Total Security is a paid security suite with a free plan and trial across Android, iOS, macOS, and Windows; its Total Security Individual plan is 59.99 USD per year for the first year, plus applicable sales tax, covering 5 devices and 1 account. Netwrix Password Secure is a paid option with no free plan and a self-service plan starting at 60.00 USD per year, with a one-year minimum purchase commitment. Proofpoint Email DLP and Encryption is a paid alternative with no free plan, available on Android, iOS, web, and Windows.

CrowdStrike Falcon Surface is a paid alternative with a free trial and a demo-based Falcon Exposure Management plan. Palo Alto Networks Cortex Cloud API Security is a paid option for API, Linux, and web environments. SentinelOne Singularity Cloud Security is paid and offers endpoint-billed plans with different data-retention terms. Cayosoft Administrator is a trial-available alternative with quote-based subscriptions for 12, 36, or 72 months. Delinea Identity Threat Protection is a paid, trial-available alternative priced by quote.

Verdict

Choose Duo Mobile if your organization needs mobile login approvals and passcodes tied to broad integrations, adaptive policies, and centrally managed authentication. Its strongest reason to choose it is the combination of flexible access controls and account-restoration support. Look elsewhere if you need a purely personal authenticator, or if your team needs more than 10 free seats without moving to a paid plan.

	Clerk	Duo Mobile
Free plan	Yes	Yes
Free trial	No	Yes
Paid from	$1.67/mo	$3/mo
Open source	No	No
Platforms	Android, api, extension, iOS, Web	Android, iOS
Free plan	Yes	Yes
Directory sync	Yes	—
Paid from	—	3 /user/mo

Clerk vs Duo Mobile

Clerk

Duo Mobile