The best replacement for arduino uno is raspberry pi.

The best alternatives to arduino uno are rated as following:
★★★★★  raspberry pi
★  arduino
★  intel galileo
  eleven

Your alternative for arduino uno is not listed? Suggest!
Speaking about arduino uno, one probably shouldn't forget about lcd.

Other search terms related to arduino uno and their ratings are:
★★★★★ lcd
★★★ labview
★★★ atmega8
★★★ atmega328
★★ lcd display
★ xbee
★ ethernet shield
bootloader
You have in mind a companion for arduino uno and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of arduino uno in all years. Click on graph for more.
arduino uno
raspberry pi
arduino