The best replacement for runkeeper is runtastic.

The best alternatives to runkeeper are rated as following:
★★★★★  runtastic
★★★★★  endomondo
★★★★★  mapmyrun
★★★★★  nike+
★★★  strava
★★★  runmeter
★★  mapmyride
★★  my tracks
★★  nike+ gps
★  mapmyfitness
★  mapmywalk
★  sports tracker
★  imapmyrun
★  gps watch
★  nike
★  map my walk
★  garmin connect
  micoach
  nike plus
  ismoothrun
  runstar
  dailymile
  walkmeter
  map my run
  digifit
  run keeper pro
  map my run app

Your alternative for runkeeper is not listed? Suggest!
Speaking about runkeeper, one probably shouldn't forget about pebble.

Other search terms related to runkeeper and their ratings are:
★★★★★ pebble
★★★★★ fitbit
★★★★ polar h7
★★★★ jawbone up
★★★★ gympact
★★★ zombies run
★★ myfitnesspal
★★ hrm
★ garmin connect
★ pebble watch
★ my fitness pal
★ withings
gym pact
You have in mind a companion for runkeeper and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of runkeeper in all years. Click on graph for more.
runkeeper
runtastic
endomondo