ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.

Outlook Google Calendar Sync - Offers calendar synchronisation between Outlook and Google, including attendees and reminders.

n8n.io - Free and open fair-code licensed node based Workflow Automation Tool. Easily automate tasks across different services.

gSyncit - gSyncit Outlook Cloud Synchronizer. Outlook Calendar, Contact, Task, Note Synchronizer supporting Google, Toodledo, Evernote, Informant, iCloud, AOL, Yahoo, Synology, Fruux, Memotoo and CalDav/CardDav services.

Zapier - Connect the apps you use everyday to automate your work and be more productive. 1000+ apps and easy integrations - get started in minutes.

EteSync - Secure, end-to-end encrypted and journaled personal information synchronization.