Lalitham is a home screen widget that displays notifications from applications you choose. The problem it addresses is that a notification from something that matters arrives in the same queue as everything else and is pushed out of view by volume.
Filtering by source rather than by content is the right approach for this, because importance is a property of who sent the message far more often than of what it contains, and a filter based on keywords fails the moment the wording changes. Widgets can be configured to group notifications from particular applications, so a home screen can carry one widget for messages and another for something time sensitive, each showing only its own sources. The privacy position is the notable part and it is structural rather than promised, since the application declares no internet permission at all, which means it is not capable of transmitting anything regardless of what any policy says. Given that a notification listener necessarily sees the content of every notification on the device, including message previews and authentication codes, that absence of network capability is the property that makes the access acceptable.
The functionality is narrow by design and it does not attempt to manage or replace the notification shade. Anyone wanting rules, scheduling, or automation is looking at a different category of application.
Link: Lalitham on Google Play