Complex sentence: With the creation of the cell phone, one was easily impressed with the mere fact that the phone required no cables, but towards the end of the 20th century, cellular phones started to modernize, and people wanted more out of their cell phones.
Split into simpler sentences: With the creation of the cell phone, one was easily impressed with the fact that the phone required no cables. However, towards the end of the 20th century, cellular phones started to modernize, and people wanted more out of their cell phones.