There's been a whirlwind of innovation since bitcoin cash liberated itself from BTC over 3 years ago, it is hard sometimes hard to keep up. So in simple summarized paragraphs I just wanted to list what I know in the way of the main additions and improvements, especially for new comers

Base protocol changes

#1 Removal of 1mb limit on blocksize. Greatly Increasing the transaction capacity of bitcoin cash, massively improving transaction certainty and lowering fees. This also prevents transaction fee market like on BTC and enables rapid 0 confirmation transactions to have more security and certainty of success. It also allowing miners to dynamically choose what the blocksize limit should be based on their costs and hardware capabilities (which is always improving at a great rate). An important knock-on effect of high tx capacity/blocksize is the energy efficiency of BCH in terms of mining energy use per transaction confirmed, currently this is approx 100x lower than BTC (assuming price parity) and is improving all of the time.

#2 Avoidance of segwit. Segwit was implemented on BTC in late 2017. It is a messy and overengineered way to increase the block size limit by a very small amount and prevent TX malleability on some BTC transactions (Tx malleability has been fixed on BCH much more cleanly with schnorr signatures) .Segwit changed BTC fundamentally from the bitcoin white paper definition of bitcoin as a "chain of digital signatures" and alters the incentives in the network as a whole.

#3 Removal of Replace-by-fee (RBF) This "feature" was added to allow people to double spend BTC more easily, it was created because transactions often get stuck on BTC due to the prohibitively small blocksize. RBF makes 0 confirmation transactions completely untrustworthy so that BTC is far less safe to accept as a means of payment in small day-to-day transactions where speed matters. RBF has been used successfully to rob businesses out of BTC

#4 Enabling op-codes To allow for smart functionality on bitcoin cash, like the creation of colored coins and representative tokens, alongside the ability to perform smart contracts, but in a more simplified and scalable manner than ethereum’s solidity programming language. This has enabled BCH to be much more than just cash, it can now perform more complex financial and legal actions by acting as a decentralized, smart and low cost platform of trust.

#5 Enabling Schnorr signatures. Schnorr signatures are a cleaner and more efficient way to sign and validate transactions, Schnorr signatures are provably non-malleable and allow multiple parties to collaborate to produce a signature that is valid for the sum of their public keys. This is the building block for various higher-level constructions that improve efficiency and privacy

#6 Canonical Transaction Ordering (CTOR) This has many efficiency benefits, especially in the context of having very large blocks. Miners no longer need to discover a valid ordering saving About 70% of block template creation time. No need to worry about intermediate states during block validation. This ensures that block validation can be perfectly parallel [3]. Ethereum’s scalability suffers from having a large number of intermediate states, for example. It makes encoding and transmitting blocks a lot easier by allowing nodes to communicate only the transactions that differ between their mempools and a recently published block. This is what Graphene [4] does, and it works very efficiently with CTOR. CTOR reduces system complexity, eliminating the entire class of attack vectors where a malicious miner can publish a large block with a transaction ordering that is as slow to validate as possible. Read in depth here

#7 Graphene Graphene, at a high level, is an efficient means of communicating new blocks to the network. The content of blocks, transactions, must be validated by others on the network. The validation process takes some time and some of the validation done by nodes can be unnecessary or redundant, slowing down block propagation. Making this process more efficient and squeezing out bottlenecks can allow bigger and bigger blocks of transactions to flow throughout the network without issues. A more efficient means of propagation means the possibility for greater transaction throughput in the future. The graphene protocol makes use of two technologies: bloom filters and invertible bloom look up tables (IBLTs). These technologies help reconcile between what a node already knows and what information it needs to know from another node. Previously, without the help of Graphene, nodes were communicating blocks to others by dumping all of the raw transaction data on them without taking into account what the node they’re communicating with already knows. Read in depth here

Secondary Protocols

#1 Cash shuffle & Cash Fusion compliment each other to enable privacy/fungibility of transactions on BCH. CashShuffle is a protocol for allowing users to combine their transactions with others, creating obfuscation. It builds upon CoinShuffle and adds a matching service. As such, it is a more complete and usable protocol. Cash fusion is Trustless, obfuscated coin consolidation.

#2 Simple-ledger-protocol The simple ledger protocol (SLP) is a token protocol for the Bitcoin Cash network, that enables anyone to create and manage tokens on-chain. The simple ledger protocol is arguably the simplest and easiest to use token token creation system across all blockchains yet. SLP tokens can easily be created, traded, and managed on the Bitcoin Cash blockchain within seconds for fractions of a penny per transaction.

#3 Smart-BCH Smart Bitcoin Cash is a sidechain for Bitcoin Cash and has an aim to explore new ideas and unlock novel possibilities. By developing optimized, high-throughput and hardware-friendly libraries compatible with the de facto standards of smart contracts, DeFi applications can be easily migrated into Bitcoin Cash's ecosystem and run fluently at low cost. It is compatible with Ethereum's EVM and Web3 API and provides high throughput for DApps in a fast, secure, and decentralized manner.

#4 Local.bitcoin.com Local Bitcoin is a private peer-to-peer platform where you can find others who are interested in trading BCH for local currencies, It is completely non-custodial and enables trades via a blind escrow smart contract.

#5 Cash Accounts https://www.cashaccount.info/ - You can send Bitcoin Cash to an easy to remember alias such as Eric#100 instead of the difficult to remember Bitcoin Cash wallet address.

#6 Scalenet https://np.reddit.com/r/btc/comments/j66eh8/scalenet_and_testnet4_are_online_and_open_for/ - Bitcoin Cash is doing the ground work to cater for Visa/Mastercard volumes level and then to be used by the entire world.

#7 Mainnet.cash - Making things easy for developers to start building on Bitcoin Cash. The codes are very simple to understand for new developers.

#8 Any hedge Decentralized derivative markets the first DeFi product on BCH

#9 Flip starter Peer to Peer crowdfunding

#10 Detoken A trustless, limitless and secure platform for accessing peer-to-peer financial products from anywhere in the world. https://detoken.net/

Smart Contract languages

#1 CashScript CashScript is a high-level programming language for smart contracts on Bitcoin Cash. It offers a strong abstraction layer over Bitcoin Cash' native virtual machine, Bitcoin Script. Its syntax is based on Ethereum's smart contract language Solidity, but its functionality is very different since smart contracts on Bitcoin Cash differ greatly from smart contracts on Ethereum. For a detailed comparison of them, refer to the blog post Smart Contracts on Ethereum, Bitcoin and Bitcoin Cash.

#2 Spedn Spedn is a high level smart contracts programming language for Bitcoin Cash. It is designed for explicitness and safety (still in development)

For a comprehensive list of services/projects see here: https://awesomebitcoin.cash/

For a comprehensive list of future and past upgrades to BCH see here: https://cash.coin.dance/development

Please comment If I get something wrong or am missing an important feature and I'll update