Those things which render the Salaah invalid

Q: Does laughing audibly with your mouth closed during salaah break your wudhu and salaah?

Q: I drank honey water. After about five minutes, I gargled my mouth but I didn't gargle the back portion of my mouth. I read my salaah and while reading, I had a sweet taste at the back of my mouth and I swallowed my saliva. Is my salaah valid?

Q: If one ate food right before praying, and can still taste the food in their mouth even though they cannot feel any food particles, just the taste, can they swallow it during prayer?

Q: If I find out something in the corner of my eyes after finishing salah, do I have to repeat it? 

Q:

1. If one finds his garment stained with blood, would he need to repeat his salah performed while wearing that garment? (bleeding due to shaving unneeded hairs and ghusl performed after that). Would his wudu be broken due to bleeding and will the clothes be considered napak? The stain was less thn an inch in all dimensions.

2. If the salaah needs to be repeated, would only the Fard salah be repeated or sunan and nawafil as well?

Q: Will the prayer be valid if some miswak fibers unintentionally remained in the mouth and were found after Salaat?

Q: Can an imam lead Taraweeh Salaah while looking at the Quran on a watch? As you know now there are smart watches. Those smart watches can automatically scroll the mushaf, so you don't even have to move or touch the screen. What's the ruling regarding this?

Q: If one’s phone rings during salaah and the ringtone is musical, can one remove the phone from the pocket and pouch in order to switch it off? If one removes the phone to switch it off, will the salaah break?

Q: What is the ruling on person who uses his hands for itching, folding sleeves, etc. during prayer? When will prayer be invalidated?

Q: What is the ruling if a person lifts up both his legs during sajdah? Is the prayer invalidated?