This Week is a lightweight and elegant Reminders client that I covered on MacStories when it came out for the iPhone, and when it was later updated to run on the iPad as well. Over a couple of updates, This Week has turned into an efficient utility to browse and manage reminders using a variety of views and filters.
With today's 1.4 update, This Week gets a night mode, a larger font option, and a plethora of URL schemes with support for x-callback-url (documented in the app). If you use apps like Launch Center Pro, Drafts, or Editorial, This Week can now be easily integrated to launch views and create reminders with or without alerts. The Night Mode is also well implemented, with settings to automatically activate it during a specific time of the day, every day.
If you're only interested in a having a different visualization of reminders (not calendar events) without natural language support, This Week is a fine app and a solid alternative to Apple's Reminders app. This Week is Universal and $4.99 on the App Store.