Amplitude PHP
How to use it
$apiKey = 123456;
$amplitudeClient = new \Amplitude\AmplitudeClient($apiKey);
$amplitudeEvent = new \Amplitude\AmplitudeEvent();
// For user properties
$amplitudeEvent->set('city_id', 123)
->set('country_id', 34);
// For event properties
$amplitudeEvent->addToEventProperties('revenue', 12.34);
$response = $amplitudeClient->track($amplitudeEvent);