The best replacement for iphone 5c is 5s.

The best alternatives to iphone 5c are rated as following:
★★★★★  5s
★★★★  galaxy s4
★★★★  4s
★★★  galaxy s3
★★  lg g2
★★  htc one
★★  iphone 5s
★★  moto x
★★  nexus 5
★★  galaxy s4 mini
★  galaxy note 3
★  iphone 4s
★  samsung galaxy s4
★  iphone 5
★  5s specs
  droid ultra
  samsung galaxy s4 mini
  galaxy s5
  moto g
  droid mini
  note 2
  samsung galaxy s iii
  google nexus 5
  iphone 4
  samsung s4 mini

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Speaking about iphone 5c, one probably shouldn't forget about siri.

Other search terms related to iphone 5c and their ratings are:

★★★★★ siri
You have in mind a companion for iphone 5c and it is not yet here? Propose!

Google Trends

Scale is based on the average worldwide traffic of iphone 5c in all years. Click on graph for more.
iphone 5c
galaxy s4