The photos printed in my photobook seem darker and not as vivid as my photos from my computer/phone

Computer monitors, notebook screens, phones and iPads are designed to make photos look vivid and bright. So manufacturers will turn up brightness and contrast as mobile screens have to remain visible even outdoors in the summer sun and computer monitors compete with harsh ceiling lights of most modern offices. You are hence accustomed to experiencing photos wiith such bright and highly saturated screens. Ink on paper reflect light to show color, whilst screens emit light to show color. So what you see on a screen simply cannot be reproduced on even the most advanced printing presses and best photo papers.