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Pro Provides a single simple and consistent API for all integrations
Segment.io's api is very easy to use, with very straightforward methods, like
Page, and each API call is hooked up to your chosen service integrations to call the equivalent method so you only need to learn one API.
Pro Most popular services supported
Segment.io has over 100 service integrations available with more being added at a steady rate.
Pro Loads in external client side services natively without proxying required
The client side segment script loads in the integration services directly so they can be used without added overhead.
Pro Easy to try out new services without requiring any changes to your page code
Segment integrations can be setup with configuration only requiring zero code deploys on your server. There is a fast turnaround time for adding the integrations that gets the new service on your site in minutes, making it very quick and easy to try out a new service while you're evaluating whether to use it. Since the scripts are loaded dynamically, it allows you to deploy new services with zero html changes so you don't have to break page caching.
Segment.io has API endpoints for mobile, browser, and server analytics, as well as a HTTP API so no matter what your analytic needs are, you can unify them all with a single service.
Pro Buffers your data playback for service integration downtime
All your historic data is stored in backup logs, and Segment.io will automatically replay your data for you to all your integrations during service interruptions like scheduled maintenance. With a business plan (requires inquiry), you can replay historic data to back fill events if you want to add a new integration, meaning your data is completely portable and can be taken with you from service to service.
Pro Raw data access
With a business level account (requires inquiry), you have access to all your raw logs that have ever been recorded.
Pro Libraries in multiple languages
Official libraries exist in the following languages and platforms for server side tracking:
All their libraries are open source, so you can follow their lead if you need to port one to an unsupported language.
Con Pricing does not work for websites
Segment switched to pricing based on price per 1000 unique user which makes it completely unaffordable for websites.