NEW YORK — Janell Burley Hofmann honored her 13-year-old son’s “maturity and growth” at Christmas with his first iPhone, but it came with strings attached.

Eighteen strings, to be exact, in a written code of conduct that placed the mommy blogger at the center of the debate over how parents should handle technology in the hands of their teens, especially younger ones just entering the frenetic world of social networks and smartphones.

Thousands of people, including those bemoaning too much helicopter parenting, commented and shared the funny, heartfelt agreement posted at the holiday by the Cape Cod, Mass., mom of five. The interest crashed her website and led her to appear with her eldest, Gregory, on morning TV.

Hofmann’s first order of business: “1. It is my phone. I bought it. I pay for it. I am loaning it to you. Aren’t I the greatest?”

She included caveats that some parenting and tech addiction experts consider crucial in easing new entrants onto Facebook, Instagram and shiny new mobile devices:

You must share passwords with a parent, answer their calls, hand over said device early on school nights and a little later on weekends. You must avoid hurtful texts and pay for a replacement if your phone “falls into the toilet, smashes on the ground, or vanishes into thin air.” Of the latter Hofmann advises her teen, “Mow a lawn, stash some birthday money. It will happen, you should be prepared.”

Hofmann said in an interview that she decided on the contract as she pondered the power of the technology she and her husband were about to plop into their son’s world. She was looking for a way to be present in his phone use without being a “creeper,” his word for stalky, spying parents.

She wasn’t surprised that her list, which Greg agreed to, resonates with other parents.

Hofmann was looking for a way to open the conversation with her son.

Hofmann also urges her boy to, “Keep your eyes up. See the world happening around you. Stare out a window. Listen to the birds. Take a walk. Talk to a stranger. Wonder without googling.”

And her final word: “You will mess up. I will take away your phone. We will sit down and talk about it. We will start over again. You & I, we are always learning. I am on your team. We are in this together.”