At least where I live in Maryland, being on "welfare" includes a cheap smart phone because a lot of jobs assume you have one for things like driving directions, getting signatures, taking pictures of receipts, etc.
If someone falls below the point where they can afford the requirements for typical jobs, then they may enter into a spiral where there is no path out of poverty.
There was a great moment of irony in my early career where lacking a job post-college ('08 reccession) I was unable to pay my student loans. 6 months after graduating I received an offer from Sallie Mae to work as an engineer, however due to corporate policy a sallie mae will not employ anyone who is arrears on their student debt.
At this point, owing approximately $2000 and only had $250 to my name which was required for rent, food, and the 18 year old ford escort that I needed to drive to work.
I was able to arrange the money, but ultimately I was within a day of being put out of work for lack of ability to pay a debt. Had this occurred I likely would not have been able to work in software, and in all likelihood the bank may never have gotten their money back on the student loans.
Either mobile data access or internet access should be, yes. You need one of those to access the job market today (among other critical services). Smartphones have become so cheap that they are most people (especially those in lower socioeconomic brackets) only computing device, and having a phone number is also a prerequisite for society, so mobile data access is the common way to gain internet access for a large swathe of society.
This is a global phenomenon too (and even more so in other countries).
I am living very comfortably but never got a mobile data plan. I find them too expensive for what they are. YMMV.