Microsoft has just recently updated their Cortana digital assistant app on Android, and if one of your complaints as a user was the sound for reminder notifications, then you're in luck as the update Changelog states that Microsoft has introduced a better notification sound for reminders. While there is obviously no reasoning for this adjustment in the changelog, logically speaking, Microsoft would likely attempt to make the notification sound for reminders better only if users had been asking for it, which could very well be the case. Of course, this isn't the only change that users can expect with Cortana in version 1.9.10.
While better sounds for notifications are can be a good thing, better functionality is a more useful improvement. With this latest update to the Cortana app, users who have it installed on a device running Android 6.0 Marshmallow will notice that the app is able to trigger reminders more accurately. If you were having any issues with reminders not triggering properly or just triggering incorrectly, then this is an improvement that should suit you well as a user.
Microsoft has improved the performance of the app as well. Following this update, Cortana's home page should load faster than before, although there is no clear description of how much faster it loads once the app is opened compared to the version of the app prior to this update. Microsoft also mentions that the home page loads better than in the app's previous version, but what exactly they mean by better is unclear. Lastly, Microsoft has also introduced a new feature that directly affects the reminder list. Now, when you want to refresh the reminder list page you can simply pull down to refresh it which is ultimately a lot easier than tapping an actual refresh button. It's possible that Cortana also got some general bug fixes and improvements with this update, although it isn't stated as such. The update for the app should already be live on the Play Store for users where this would be a first time install and for existing users the update should show up in your my apps list within the Play Store app.