My lab is doing a study of how parents select educational apps from the app store. We have posted the survey to facebook and have boosted it. Nothing. Any ideas on how to reach participants online would be helpful.
U may try twitter with some popular hashtag. U can mention #academictwitter or #academicchatter u may find Apple to retweet. If u are in uk you may decide to post it on helpfulpeeps.com
You may also try to post on some FB parenting groups after taking admin permission.
I've used Prolific.ac for online surveys. You can sample participants based on various criteria --- not sure if parenthood is there, but even if it's not, you can include mention of it in the study title, like "Study about parenthood (*parents only*)". Should help you get the people you need.