Planned obsolescence yes however so is nearly every other tech device yet you can get a smartphone for free with a data/calls pakage and if you're attentive and patient you can find deals that'll clip the first six months off your bill, essentially. Grabbing an 700 euro smartphone ever 12-18 months for around 400 euro in total with unlimited data and service for that period.
Use that smartphone for 6 months then smash it with a hammer, wait a week and tell me how it's effected your life.
That is money and tech well used. The ease of life applications are fucking awesome.
I bought mine for a 100 quid and pay 5 quid a month for data/calls with no contract so can skip paying for months if I'm not using it or whatever.
But yeah, 400 euros every years sounds like a great deal...