Nowadays it became custom than everyone owns a phone. What is the ruling on a man refusing to get a phone for his son, daughter and wife for no reason just because he does not like to spend on them anything beyond bare minimum? Considering the son and wife have no money and it customary for people like them to be bought a phone by the man?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu 'alayhi wa sallam, is His slave and Messenger.

At the outset, two important considerations need to be highlighted:

First: There should be mutual understanding and respect between spouses to avoid conflicts and disagreements and to maintain the primary goal of marriage, which is psychological serenity and stability.

Allah says (what means): {And of His signs is that He created for you from yourselves mates that you may find tranquility in them; and He placed between you affection and mercy. Indeed, in that are signs for a people who give thought.} [Quran 30: 21]

Second: The husband should generously provide for his family according to whatever Allah has given him. This generosity not only pleases his family but also shows gratitude towards Allah, the Almighty, for His blessings. Spending on one’s family is considered one of the best forms of charity. The Prophet, sallallaahu 'alayhi wa sallam, said: “(There is) a dinar you spent in the cause of Allah, a dinar you spent to free a slave, a dinar you gave as a charity to a poor person, and a dinar you spent on your family; the greatest of these in reward is that which you spent on your family” [Muslim].

The wife deserves particular kindness and generosity. ‘Aa'ishah he best of you is he who is best to his family, and I am the best among you to my family.” [Recorded by At-Tirmidhi, who ranked it as Hasan Sahih (Good and Authentic)].

Regarding financial obligations: Purchasing phones for the wife or children is not considered as obligatory maintenance (Nafaqah). Common practice does not make it obligatory. According to the majority of jurists, obligatory maintenance typically includes only essentials such as food, clothing, and shelter, as asserted by Imam Muhammad Ibn Al-Hasan Ash-Shaybani. (See Al-Bahr Ar-Ra’iq).

Even if it is supposed that a phone is deemed to be needed, the husband is not legally required to meet all desires of his wife and children. He may choose not to buy a phone for his wife or child if he perceives a benefit in this decision or aims to prevent potential harm.

Allah knows best.