Qik
At home we use several apps: Wunderlist for shopping, Dropbox for file sharing, shared calendars, custom library manager I wrote over a decade ago and we often use our own websites for notes or cooking recipes.
There are tons of cool stuff you can do with recipes, with proper data pool, of course. It can suggest meals to cook, considering recent meals. You can look for a meal according to ingredients you have. You can cap those meals by calories or require certain dietetic restrictions.
You can create a weekly dishes and calculate efficient grocery shopping for required ingredients.
Qik Logo
There are also many other things the family could share, like contacts, business hours, schedules, copies of receipts and invoices, stock of toiletries or cleaning products or even food expiry dates for long-term products.
I don't really see anybody keeping an eye on food expiration dates, it just requires too much effort. This is a task for AI/ML, but that's a story for another day.
And more good news, some modules from Quid are compatible with Qik.