Blockchain Programming in iOS Using Swift (Udemy.com)

I have taken several courses presented by this instructor. With my interest in Blockchain technology, I decided to buy this course to learn about programming the technology in a Swift environment. Though there is much more to learn about Blockchain, I have a stronger developer perspective of it as I move forward. I definitely recommend the course. There is a small caveat: some code is out of date. I did not mind doing research to bring the code current.

The content and theory is good, you get to learn Proof of Work principles and how to generally implement a rudimentary PoW blockchain. However, the course is not updated for Vapor 4 and Swift 5 (use of controllers in Vapor 4 and async/await in Swift 5). The smart contracts video is not updated and so the smart contracts in playground doesn't work you'll have to look into the end files. Last point, although the resolution method works and gives one an idea of how it works but definitely not possible for production. I understand a course wouldn't be able to teach you all the facets for production level blockchain but generally from course to production should just be a few admin actions, instead of glaring loopholes. In closing, if you are interested in a general idea of how to implement a blockchain this works. I appreciate the time and effort put into making this!

It is a nice course that lets you see how the blockchain (in its simplest form) may be implemented. There are some cons though, like excessive repetition and redundant things (like launching the app and waiting for the Genesis block to be created - so many instances). What I think is lacking also is a demo of the blockchain resistance to the malicious attack (immutability). The shown `resolve()` method is not enough, hashes should work in this process as well.

Very nice course. Enjoyed it very much as it brought me nearer to understanding BlockChain Technology. It would be great to have an update for the current vapor version as that code did not work on the newer version. Please take the next as an personal observation and not a complaint. I had to raise the speech speed to 1.5 and 1.75 because the normal speed was so slow. I noticed that I started nodding off after3 lectures.

Thanks for this amazing tutorial on the blockchain, I stereotyped the concept of blockchain is very complex to understand but you demystify it with so simple examle that I learned all the blockchain concepts like block, genesis block, proof of work, smart contract, decentralized blockchain, etc. I got a clear understanding of how to use Vapor framework for web apis as well. I really inspired to learn more about the vapor web API framework .

This course is a good intro / primer to experimenting with Swift and blockchain. As the course began, I chose to implement a lot of the blockchain models in a dynamic framework (instead of a playground). This paid off later on in the course, when we switched to Vapor - it was a matter of including the dynamic framework in multiple targets (one for iOS, one for the Vapor node). I highly recommend doing this if you know how to, it saves you a lot of playground compilation headaches. If you have any prior blockchain experience, there are several instances where the object model used in the course seems a little basic. For example, the concept of difficulty is explained and actually implemented, but the purpose is to just cause the hashing function to run for a longer period of time so you can see it "work". Other than being used to show a simulation of what mining a block would be like, it's not really used in a practical way. This leads one to ask, why include it in the course? Unless your nodes are automatically rebalancing the rate at which blocks are computed with other nodes in the network to avoid surges in hash rate, this could probably be left out. Overall the instruction is pretty clear and concise, and if you've been looking at something Swift-specific, this is a great start.

Great explanation of the basics. But leaves many questions unanswered. For example, in the course the mining and sanding transactions are treated as the same thing, this confuses me. I would love to hear how exactly sending some amount of crypto currency, fits into the blockchain process. And how does the sum validation happen, etc. Overal I enjoyed this course and I think it was well worth the price.

First. I have to say this is a very good lecture. But there are some mistakes that shouldn't happen and corrected in an extra lecture in my option. Eg: 1. forgot to add block to the chain for the getnextblock() function and record another lecture to correct the mistake. 2. forgot to add block to the chain again in another lecture and recorded extra lecture to correct the mistake. 3. add transaction twice and corrected the mistake in later lectures. Those are just small mistakes but confused me a lot. I had to re-take the lectures again because I was not even sure whether it's a mistake until I finished the next lecture which corrected the mistakes of the last lecture. Anyway, the lecturer is kind enough and well experienced and answer my questions patiently

After getting used to the presenters voice it is super to follow the coding parts in this tutorial also nice getting into touch with server side swift wish to learn sth about peer-to-peer connections now...

Still very good to see the basics of the blockchain, blocks, and transactions done in code. Some of the information is incorrect, such as the starting and current mining reward per block (in 2018 it is 12.5BTC, and it started at 50BTC), and the genesis block wasn't set up to produce rewards, it was set up to produce a block holding the first transaction by Satoshi. The "Coinbase transaction" is what produces the reward, and that is the first transaction in every block.