Reading/Web/EventLogging best practices

Also see WMF wide EvetnLogging best practices: Extension:EventLogging/Guide

Schemas

 * Schemas in MobileFrontend should be prefixed with `MobileWeb`
 * The talk page should be edited with the `SchemaDoc` template. For example Schema_talk:MobileWebSearch

Sampling rate

 * When logging events that occur on every page view a sampling rate of 0.1%
 * When click tracking events on prominently used features, 1% is usually enough e.g. clicks to menu items or search usage (given that not all page views result in an event).

Use of session ids

 * Some events need to be linkable to other events, for example Schema:MobileWebSectionUsage records clicks to section headings in a given user session. This is usually done via a unique token that is generated once and used until the user closes the browser.
 * In some situations where workflows span multiple pages it may be necessary to persist such a token a little longer. When this is the case please ensure you minimise the duration the session is stored for.