I'm trying it yet again (millionth time, because of all the injury). I'm still getting shin problems and really tight/cramp calves, but I'm taking it much more slowly than you're supposed to, just increasing it really gradually, so I have actually made it to week 4, without unbearable pain at least.
I started using a couch25k app, but it moved too fast after week 2, so I've now downloaded an interval trainer, and have used the weeks from couch to 5k as a guide, and made about 10 steps in between each week, to get me from one to the next. It took 12 steps to get from week 3 to 4, and I'm just starting on the ones I've done for week 4. I made 10 steps but I am sure I will have to repeat some of them, as I just can't seem to build up the stamina. Each time increases one of the runs by 15-30 sec, or reduces one of the walks. Even after about 4 months of this, I still find 3 or 4 minutes a real struggle when it gets to the second or third time. I know I'm unfit, but I really thought I'd be improving a little faster!
I also downloaded map my run, and found that my 30 min walk/jog is only about 3km, so I'm going to have to increase that quite a bit as the jog part increases if it's going to get to 5k in the end. At the moment the thought of increasing it to 6 or 7 minutes, which is what I have to do as part of this lot of workouts, is daunting.
I like having all the apps, though, telling me where I am every 30 sec or whatever, seems to make the time go faster, and I can push on for that extra bit. The first app would only tell me every minute, and that wasn't enough, but I think I've set Map my Run to tell me every 30 seconds, which might help. It's towards the end of each minute that I start to lose motivation.