<a href="http:&#x2F;&#x2F;2doapp.com" rel="nofollow">http:&#x2F;&#x2F;2doapp.com</a> can filter by location and tag.  Tags can be paused&#x2F;unpaused and there are SmartList (saved search filters).  Available on Mac, iOS, Android and will sync to 3rd-party or self-hosted open-standard CalDav servers, in addition to the usual cloud services.