I found this free app called Couch to 5K & 10K by App Symphony on the Google Play store, whose C25K component mirrors that of the NHS. The voice guidance is very robotic and concise merely instructing when to run and when to walk rather than offering encouragement and platitudes. It does, however, allow you to use other apps on your device such as VLC Media Player or Spotify to listen to your own music and podcasts, which it will interrupt briefly with instructions to walk or run before letting you continue your listening and activity.
App For Beyond C25K: I found this free app... - Bridge to 10K
App For Beyond C25K
Thanks for posting. Are you planning on following this one?
I do plan on using this Couch To 5K & 10K app when I start contemplating the 10K level, but it will be a few weeks before I complete C25K a second time in as many years. Then I want to do a month of consolidation runs to become totally comfortable with 30-minute runs before progressing to longer times & distances. I like this app's incremental approach towards 10K, starting with four 10-minute running segments separated by 1-minute walking intervals, exactly the approach of C25K that got us off the couch in the first place. This eases us into 40 minutes of total running from the 30 minutes where C25K ended. Whilst I haven't explored other post-5 K plans, this one resonates with me.
Presently, I'm training to individually downloaded episodes of the NHS's C25K podcasts which I play back using my device's media player. The NHS's free app which may have a 10K feature isn't available outside of the UK. My workaround installing a 3rd-party APK proved problematic as it was full of static & interruptions that are disruptive to a session of running.
I am testing the 5K component of this Couch To 5K & 10K app & finding it to work quite well if not a tad clinical compared to the friendly mollycoddling by the coaches of the NHS podcasts. Each session's interface has an icon which when pressed pops up a written description of that session. I get the impression that some sort of text-to-speech tool in conjunction with a countdown timer or stopwatch is merely reading out this note when you hit the 'play' button. It shouldn't be a bother, however, as you're entertained for the duration of your session by your own music, podcast or audiobook through whatever app you use normally whilst the Couch To 5K & 10K app runs simultaneously in the background. I do recommend downloading your private entertainment to play off-line as interruptions to streamed content due to poor connectivity can be terribly annoying when you have to stop & fumble with reading glasses, devices & a tangle of headset chords with sweaty fingers.
I use Runkeeper as my primary app which uses GPS to map runs & compile statistics. The Couch to 5K & 10K app above is bare-bones & primitive & doesn't do maps & stats. Quandary indeed so I tweaked things a bit. Runkeeper which has voice prompts that you can choose to activate, allows you to customise a session. Using the programme outlined in the Couch to 5K & 10K app, eg. week 1's three sessions of four 10-minute runs separated by 1-minute walks, I went into the custom run menu of Runkeeper & set up the above W1 sessions. It worked well. The voice prompts of Runkeeper are rather dry but I had a Spotify podcast entertaining me in the background. I could also have been playing music or other content through the device's media player. Runkeeper interrupts whatever other app you're using with instructions to walk or run, then returns you to your listening on the background app. I completed W1 of the Bridge To 10K this way & all went swimmingly. Today, Parkrun, then W2 of B210K.