By the look of it you did good job how you communicate with your users using email, and you tried various methods to attract more attention.
Saying that you do not mention you user base specifics. I could only assume what could be the issue here, and try to suggest some of the best practices.
One of the factors to consider is value to the end user.
- Is information useful or overwhelming?
- Are you re-connecting with the real user, making it personal and engaging, human like?
- Is "Important announcements" equals to release notes? If so, if your app designed well - users should be able to figure out and use it without any training. If that's not the case, perhaps it's worth revisiting and adjusting design with users in mind.
only use the app on a bi-weekly or monthly basis, so they miss some of
Based on the above I could only suggest looking into passive notification, if it course possible to implement.
Passive notifications are informational; they report a system
occurrence that does not require any user action. Many notifications
in mobile apps are passive: they usually announce an event of
potential interest to the user.
- Passive notifications are typically not urgent and should be less
- A typical implementation of a passive notification may be a badge
icon or a small nonmodal popover in a corner of a screen.
- Passive notifications can easily be missed, since they require no
When the information provided by the notification is key to the understanding of the system, an easy-to-ignore passive notification can be problematic.
Notifications have the design challenge that they are not the
immediate and obvious result of a specific user action. On the
contrary, the user is likely in the middle of doing something
different and may not be thinking about the issue raised by the
notification. This requires notifications to establish more context
and provide users with sufficient background information to understand
what the notification is about.
If a notification is contextual and relates to a specific element in
the interface, an icon indicator on the element can communicate where
that notification applies and catch the user’s attention. For
instance, an indicator badge on a mobile-app icon shows that the user
has received a notification from the corresponding app.
Mint.com used an indicator together with a notification to communicate that an account needed attention. The warning indicator (1) appeared in close proximity to the summary of the account that needed attention, while the notification (2) appeared in the central area of the page with other important information. The actual text in the notification message could have been more helpful, though.
Also, I would suggest looking into how slack operates they notes.
Why they’re important to us, and how we approach the writing of them
Few interesting ideas and suggestions which might be useful.