Amazon offers the Logitech K380 Multi-Device Bluetooth Keyboard for $29.99 with free shipping for Prime members or on orders of $35+. That's $10 (25%) below its regular price and a match for the best we've seen. It can connect to up to three compatible devices (iPhone, iPad, Mac, PC, Apple TV, Android smartphone/tablet, more) at once and "switch between them at the touch of button." The 2 included AAA batteries provide enough juice to last up to two-years. Rated 4.3 out of 5 stars from 64 Amazon reviewers. Available in Dark Grey or Blue.
Looking for a dead-simple mobile keyboard? Belkin's MFi Lightning iPad is on sale right now for $34 Prime shipped (Reg. $60).
- Multi-device Bluetooth keyboard: Universal keyboard for typing on all your computing devices*: Windows, Mac, Chrome OS, Android, iPad, iPhone, Apple TV 2nd or 3rd generation (*Any Bluetooth-enabled computers or mobile devices that support external keyboards with HID profile. Check with device manufacturer for details)
- EasySwitch: Connect up to three devices simultaneously and switch between them at the touch of button
- Compact mobile keyboard: Easy to carry around your home for familiar typing in any room
- OSadaptive: Automatically recognizes each device and maps keys to give you a familiar layout, including shortcuts
- Two year battery life*: Virtually eliminates the need to change batteries (*Keyboard battery life calculation based on an estimated two million keystrokes/year in an office environment. User experience may vary.)