Here’s my recipe to light up “ok Google, add eggs to my list” and have my Google Home add the item to my family’s shared grocery list on Wunderlist.
Bear with me, as there are a few steps. We’ll be using the Mail to Wunderlist feature (where you can send emails to firstname.lastname@example.org and they get added to your list), with IFTTT, since there is no direct Wunderlist action for Google Assistant.
First you’ll need a Wunderlist account, duh.
Next, add an email address to Wunderlist at the email settings page. I suggest using a desktop computer for this step, as Wunderlist’s site on mobile may be different. If you must do it on Mobile, try it in Chrome and use “request desktop version”. Final piece of advice: I suggest using an email account here that you trust to give IFTTT complete access to (which is the next step), I personally chose an old address that I don’t use for anything much. It’s not that I don’t trust IFTTT specifically – I basically just don’t trust anyone except my email provider with my email account. You’ll need to verify this email address by clicking the link in the email Wunderlist sends you.
Now go to the Mail to Wunderlist setting. Beside your email address, select the Wunderlist you wish incoming emails to go to (e.g. “Family groceries”).
The rest you can do on your phone, which I recommend. Open the IFTTT app, and create a new recipie.
For the “IF”, select Google Assistant. For the phrases, I used “add $ to my list”, “add $ to my shopping list”, “add $ to my wunderlist” but feel free to improvise. “Ok, added $ to your list” is the response I chose. For the THEN part, choose send an email, and link Gmail selecting the account you configured with Wunderlist above. The to address is “email@example.com”, for the Subject choose the recipe “TextField”. CC yourself for debug purposes if you need.
That’s it, you’re done. Try it out on your home, with “OK Google, add eggs to my list”.