Hi Burak,
Hacking is a great moneymaker. My Sims all have a level 10 in Programming, and Supercomputer (level 10) is a great source of money §500 or §550 --- or more as a surprise, Crumplebottom (level 10) usually nets about §600, Plumbook (level 9) about §450, National Sims Security Agency (programming level 7) about §350 --- each time a Sim hacks something. There are 3 companies that Sims can hack at a lower level of programing --- by level 2 hacking one of them is available, as well as two others at levels 3 and 5.
If too many of your Sims hack the same company on the same Sim day, then, that company is temporarily greyed out --- try again the next day or two days later.
Apps make you money once a week, but only between §7 and §12 --- but it is weekly, and I have 6 Sims in the Tech Guru career.
I think plug-ins (level 2 Tech Guru) make about §30 one time --- paid once per plug-in, but you can have your Sims make several plug ins in the same day.
Making a computer virus (level 4) makes more than plug-ins, and pays your Sim once for each completed virus, as well.
Freelance Work (level 5) gets between §300 and §600 and pays your Simsm once for each completed job.
