Baikal
Your calendars and contacts do not need a cloud account, and Baikal is the small PHP server that keeps them on hardware you control while still syncing to every phone and laptop you own. The web admin panel is where you add users, create their calendars and address books, and reset passwords, no database editing or config files required. Each person signs in with their own username and password, so an iPhone, an Android phone running DAVx5, and a Thunderbird desktop can all stay in sync without sharing one master credential. Standard well-known redirects mean most clients configure themselves when you type the server address, and the combined dav.php endpoint serves calendars and contacts from a single URL. Events carry the full CalDAV feature set your clients expect (recurring appointments, reminders, attendees, and free-busy lookups), while CardDAV address books keep names, phone numbers, and photos in one place. Because storage is a plain database file or table set, backups are a copy you can make in seconds, and moving to a bigger host is a file transfer rather than a migration project. The same server happily runs for one person tracking a family calendar or for a small office sharing team schedules and a company address book. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. GPL-3.0 licensed.
SOGo
SOGo adds shared calendars, address books, and a modern webmail interface to your existing Dovecot, Postfix, or Cyrus mail setup, turning familiar infrastructure into a full Exchange competitor. Rather than replacing your IMAP and SMTP servers, SOGo layers collaboration on top of them, becoming the missing link between raw mail delivery and what users actually expect from a workplace communication platform. The ActiveSync implementation synchronizes email, contacts, calendars, and tasks natively with iPhones, Android devices, and Windows without requiring users to manually configure CalDAV endpoints. CalDAV and CardDAV compliance ensures Apple Calendar, Thunderbird (via the official SOGo Connector extension), GNOME Evolution, and Android via DAVx5 all connect without plugins or workarounds. The web interface uses AngularJS Material design with responsive layouts, offering folder management, drag-and-drop calendar scheduling, contact groups, resource booking, and delegation. Shared calendars support free-busy lookups, iMIP event invitations, and per-user ACL permissions for fine-grained access across organizational units. Built on Objective-C with the GNUstep foundation, SOGo delivers exceptional performance: hundreds of concurrent ActiveSync connections from mobile devices alongside webmail and calendar traffic with sub-second response times. With 2,095+ stars and 116 releases, the project has proven its stability in production environments supporting thousands of users. The Docker deployment runs alongside PostgreSQL and memcached.
bewCloud
A personal cloud does not need the weight of a small enterprise suite, and bewCloud proves it by keeping files, photos, notes, contacts, and calendars in one compact service a single person can run for a whole household. The Files app stores uploads in a plain folder tree on disk, offers public sharing links, optional whole-folder downloads as zip archives, and a WebDAV endpoint that desktop tools can mount. Photos turns that same storage into a browsable gallery, while Notes keeps quick text within reach of every login. Contacts and Calendar speak CardDAV and CalDAV through a bundled Radicale server, so the calendar and address book on a phone or laptop stay in sync without another account anywhere. News collects feeds to read in the browser, and Expenses tracks spending in a small ledger beside everything else. The header shows only the apps you enable, in the order you choose, and companion desktop and mobile apps connect to the same server for people who prefer native sync. Accounts can be protected with multi-factor authentication using TOTP, passkeys, or email codes, and optional single sign-on lets a household sign in through an existing identity provider. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.
Nametag
CRM mechanics applied to your actual relationships instead of a sales pipeline: Nametag is a Personal Relationship Manager (PRM). It exists to fix the things you keep forgetting: when you last talked to an old friend, their kids' names, the birthday you missed twice. Contacts are tracked with flexible attributes - names, birthdays, important dates, and free-form notes for everything else - and organized into custom groups. Where it goes beyond a contacts app is relationship mapping: you define how people connect to each other (family, friends, colleagues, or custom relationship types), and an interactive D3.js-powered graph renders your entire personal network so you can see clusters and connections at a glance. Staying in touch is automated: scheduled reminders fire for birthdays, important dates, and reach-out nudges, with optional email delivery via a Resend API key for password resets and reminder notifications. Built with Next.js, it is mobile-responsive, ships with full dark mode, and supports multiple languages including English and Spanish. Because it is self-hosted, there are no account tiers or contact limits - unlimited people and relationships, with every note about your personal life stored on your own server rather than a social-graph company's cloud. A lightweight, single-container deployment makes it one of the easiest personal tools to run.
Meerkat CRM
Friends drift away when nobody remembers to call; Meerkat CRM is a self-hosted personal CRM that keeps your relationships warm with birthday and stay in touch reminders, contact notes, and a living map of who knows whom. Organize every contact into circles like family, friends, or work, store spouses and children as linked relationships, and see the whole crowd on an interactive network graph that shows how people connect. Sync the same address book two ways: Meerkat runs its own CardDAV server for your phone and can also act as a CardDAV client against an external server you already use. Against each person you can keep the details that matter, dietary habits, kids names, the last conversation, plus a social style timeline of activities you have shared, from dinners to group projects. Reminders nudge you by email when it has been too long, with upcoming birthdays surfaced on the dashboard, so catching up becomes a habit instead of an afterthought. Move data in and out freely: import CSV, VCF, and even a Monica export, export back to CSV and VCF, connect external calendars, and fire webhooks into your own automations. Use it in English, German, Italian, Spanish, or French with light and dark modes, and SSO for whoever shares the house. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.
Radicale
Calendars, to-do lists, journal entries, and contacts, synced over the open CalDAV and CardDAV standards nearly every client already speaks: Radicale is a small pure-Python server that works with Thunderbird, DAVx5 on Android, Apple Calendar and Contacts, GNOME, and many more. Its defining design choice is radical simplicity: there is no database. Events live as plain .ics files and contacts as .vcf files in an ordinary folder structure, which makes backup a copy command, migration a move, and disaster recovery a matter of reading text files. The server works out of the box with no complicated setup, then grows as needed: flexible authentication (htpasswd files among other methods), per-collection authorization rules, TLS-secured connections, and a plugin system for extending storage, auth, and rights handling. Built-in limits on parallel connections, file sizes, and failed authentication attempts harden it for network exposure behind a reverse proxy. A bundled web interface handles creating and managing calendars and address books - useful since many clients cannot create collections themselves. Maintained since 2011 with 140+ contributors, GPLv3-licensed, and light enough to run on the smallest VPS or a Raspberry Pi.
Gofer
Five mailboxes, five tabs, five passwords: Gofer folds Gmail, Outlook, iCloud, and plain IMAP accounts into one browser tab where every inbox reads as a single, searchable whole. Threads, labels, and drag and drop keep triage fast, and search still finds the receipt from three years ago. Signatures and custom senders shape outgoing mail, scheduled sends wait for Monday morning, and a thread in another language translates in place. The calendar keeps pace with your mail: Google, Outlook, and CalDAV events sync both ways, invitations land in the inbox, and an RSVP or a Meet or Teams link attaches without leaving the message. Contacts follow the same rule through Google, Outlook, and CardDAV sync, so the address book you fix once is right everywhere. One install can serve a household or a small office, with separate users, encrypted credentials, blocked remote images, and passkey or authenticator sign-in for anyone who wants it. Classic, Minimal, and retro Express themes, flexible layouts, and push notifications make the daily inbox feel personal rather than administered. Leaving stays easy too: mailboxes export as mbox, mail moves between accounts, and a whole setup imports into another Gofer. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.
Kurrier
Kurrier unifies email, calendars, contacts, and file storage in a single web interface that connects to any email provider you already use. The Next.js frontend with Nitro API worker deploys via Docker Compose on PostgreSQL and Redis, delivering a cohesive workspace where IMAP/SMTP mailboxes from Gmail, Outlook, or corporate servers sit alongside transactional providers like AWS SES, SendGrid, Mailgun, and Postmark. Automatic inbox building handles threads, attachments, sent items, and deletion sync through persistent background polling. The CalDAV backend enables full two-way calendar synchronization with iOS, macOS, Android via DAVx5, and Thunderbird, supporting event invitations, RSVP processing through the inbox, timezone-aware scheduling, and contact-aware attendee linking. CardDAV contacts sync bidirectionally across all devices with unified name, avatar, and email resolution. Kurrier Drive provides integrated file storage through WebDAV locally or S3-compatible backends for cloud storage. Multiple identities and domains let you manage several email accounts from different providers in one interface, with fast local search indexing subjects, senders, and content without dependency on external APIs. The API-first architecture exposes clean endpoints for automation and custom integrations. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.