Compare K-9 Mail vs. Letterbox

Secure your company’s communications with Proton Mail — the business email solution trusted by over 50,000 organizations. With end-to-end encryption built in, your internal and external communications stay confidential by default. Proton Mail helps your business meet GDPR, HIPAA, and other compliance standards, while giving you full control over your data under strong Swiss privacy laws. Empower your team with encrypted email and calendar, support for your custom email domains, professional branding, and simple migration from providers like Google Workspace or Microsoft 365 — no IT team required.

Proton Pass for Business is a privacy-first password and identity manager that helps organizations secure access at scale without sacrificing usability. Built with end-to-end encryption and a strict zero-knowledge architecture, it ensures that passwords, passkeys, secure notes, and payment details remain accessible only to authorized users within your team. Not even Proton can view your data. Teams can securely create, store, and share credentials via encrypted vaults, enabling safe and efficient collaboration. Granular admin controls allow IT managers to oversee permissions, enforce strong password policies, monitor access, and manage users throughout the employee lifecycle from onboarding to offboarding. Built-in password generation, autofill, and cross-device syncing streamline everyday workflows while maintaining high security standards. Proton Pass for Business also includes advanced features such as email alias integration to protect employee identities, dark web monitoring to detect compromised credentials, and detailed activity logs for visibility and compliance. Its open-source foundation promotes transparency and trust, and independent audits reinforce its security model. Hosted in Switzerland and protected by strong privacy laws, Proton Pass offers organizations a secure alternative to traditional password managers. With seamless browser extensions, an intuitive design, and enterprise-ready controls, it empowers teams to reduce credential-related risks, prevent unauthorized access, and improve productivity, all within a secure, encrypted environment.

BrandMail®, created by BrandQuantum, is an innovative software tool that integrates seamlessly with Microsoft Outlook, enabling all employees within the organization to automatically generate emails that consistently reflect the brand through an easy-to-use toolbar that grants access to brand guidelines and the most current pre-approved materials. With this solution, email signatures are crafted according to your branding requirements, ensuring a uniform appearance regardless of the device or platform used to view them. These signatures are secure and managed from a central location, providing peace of mind regarding their integrity. Notably, users can view their signatures, banners, and surveys when composing, replying to, or forwarding emails. Unlike other solutions, BrandMail does not redirect emails through external servers nor does it modify the rules within your exchange environment, functioning entirely within Microsoft Outlook. By utilizing BrandMail, organizations can turn every email into a branding opportunity while also reducing the security vulnerabilities linked to the manipulation of HTML signatures, thereby enhancing both brand consistency and cybersecurity. This not only streamlines communication but also reinforces the brand identity across all employee interactions.

PostScan Mail is a virtual mailbox service that provides individuals and businesses with a convenient and secure way to manage their postal mail online. With PostScan Mail, users can access their physical mail from anywhere in the world through their digital devices. The service allows users to view and manage their mail, receive notifications of new mail items, forward mail to any address, scan and shred unwanted mail, and even deposit checks remotely. PostScan Mail eliminates the need for physical mailboxes and offers a practical solution for people who are always on the go or live in multiple locations. It is a modern and efficient way to manage your postal mail, making your life easier and more streamlined.

DirectMail2.0 maximizes omnichannel performance by integrating the latest mailing technology with real-time reporting and digital components to lift response by 25-50%. Our omnichannel ecosystem currently includes 15 features, all managed from a single dashboard that reports real-time campaign results, both offline and online.

Click2Mail transforms traditional mail with its online and on demand, SaaS print to-mail service. Click2Mail gives users access to tools that make it easy to create and mail postcards, letters, and other printed materials. Individuals and organizations can use Click2Mail's easy-to-use Mailing Online Publisher to create, address, and ship mailpieces from anywhere on the globe.

Microsoft 365 is a comprehensive productivity suite that brings together essential tools like Word, Excel, PowerPoint, Outlook, and Teams in a unified cloud-based environment. Enhanced by Microsoft 365 Copilot, the platform integrates AI directly into these applications to help users work more efficiently and intelligently. Users can quickly generate documents, analyze complex datasets, and design presentations with the help of AI-driven suggestions and automation. The platform supports real-time collaboration, allowing teams to work together on files, share updates, and communicate seamlessly. With OneDrive cloud storage, users can securely store and access their files from any device at any time. Microsoft 365 also enables users to incorporate their own files into AI prompts, ensuring responses are relevant and context-aware. Copilot can assist with brainstorming ideas, summarizing content, and organizing workflows to save time. The platform is accessible across desktop, web, and mobile applications, providing flexibility for different work environments. It also prioritizes user control, giving individuals the ability to manage how AI is used within their workspace. By combining productivity tools with intelligent automation, Microsoft 365 helps users accomplish tasks faster and more effectively. Ultimately, it empowers individuals and teams to improve productivity, collaboration, and decision-making in a modern digital workspace.

Secure your organization from costly data breaches while meeting essential compliance requirements, such as ISO 27001, GDPR, and HIPAA. Our software-based VPN solution is easy to deploy alongside your existing systems, giving you a powerful and adaptable tool for securing your enterprise network. Our VPN Professional plan allows your team to connect securely to your local networks and cloud-based services. And with granular segmented control over who can connect to dedicated VPN servers and Gateways (logical groupings of dedicated servers), you can ensure your staff can access the resources they need (but only what they need). All of our business plans use robust industry-standard AES-256 or ChaCha20 encryption to ensure your data remains secure. You can further strengthen your organization's security with enforced two-factor authentication (2FA) and seamless login through single sign-on (SSO) with SCIM support for automated user provisioning. Our global high-performance (mainly 10 Gbps) server network is one of the largest in the world, and is part of the trusted Proton ecosystem — a suite of fully open source, end-to-end encrypted services built by the creators of Proton Mail and designed specifically to keep your business secure.

ESET Protect Advanced offers a comprehensive cybersecurity solution for businesses of any size. It offers advanced endpoint security against ransomware and zero-day threats. It also includes full disk encryption to ensure legal compliance and data security. The solution uses adaptive scanning, cloud sandboxing and behavioral analysis for proactive cloud-based threats defense. Mobile threat protection secures Android and iOS with anti-malware and anti-theft. It also offers cloud app security, mail server protection, vulnerability and patch management, and cloud app protection. Multi-factor authentication and extended detection and reaction (XDR) improve threat detection and response. The solution provides a single pane of glass remote management to provide visibility into threats and users. It also offers advanced reporting and customized notifications.

NewOrg is a robust platform that allows non-profit organizations to integrate information from all areas of their operations. This allows them to better manage clients, volunteers, services, donors, donations and outcome. It also provides the ability to schedule activities, sign-ups, communications, surveys and fundraising activities. NewOrg is a powerful platform that can help you manage your committees, donors, events, and memberships to ensure that your organization runs smoothly.