77% in developed world are happy but wish life was simpler, says poll

Survey of 16,000 people finds widespread contentment, but few optimistic about prospects for the planet

There’s a fitness tracker for vaginas. Quantifying your life has gone too far

Jess Zimmerman: Biofeedback is great ... right up until you use it to get positive feedback from everyone you know

Fitbit flex wristband review: a weight loss tracker that makes fitness a habit

Counting steps and calories adds up to shedding 5lbs sensibly

Jawbone Up and Sleepio app review: use your smartphone to get a good night’s sleep

The wristband collects your sleep data and the app helps you to learn new habits, while online tutorials give useful suggestions

Zepp sensor review: a racket-mounted app that can improve your tennis

How to capture, measure and analyse your swings in three dimensions

KGoal: introducing the fitness tracker for your vagina

Wearable technology conquers the final frontier with KGoal, a device to help women the world over exercise their pelvic floor muscles better

If you want a better, happier life, here are 10 apps that could help

Dr Lucy Maddox, an NHS clinical psychologist and lecturer, picks the best psychology apps

Attacks on breastfeeding mothers speak to a far bigger online problem

Rebecca Schiller: The abuse generated by a picture of a student breastfeeding at her graduation is an indication of the scale of woman-shaming on the web

Apple unveils move towards health and home in new iPhone software

Software will gather and store health-related data and offer integrated control for 'smart home' devices like lighting

A carbon fibre e-bike: built for Batman

Karl Mathiesen: It's cool, futuristic and packs in serious gadgetry – with a matching price tag, but is it a smart city bike?